Monoalkyltin compounds with low polyalkyl contamination, their compositions and methods

Abstract

High-purity compositions of monoalkyltin triamide, monoalkyltin trialkoxide, or monoalkyltriamidotin, and methods for producing them. [Solution] The present invention relates to a composition comprising a monoalkyltin trialkoxide compound represented by the chemical formula RSn(OR')3 or a monoalkyltin triamide compound represented by the chemical formula RSn(NR'2)3, and a dialkyltin compound in an amount of 4 mol% or less relative to the total amount of tin, wherein R is a hydrocarbyl group having 1 to 31 carbon atoms, and R' is a hydrocarbyl group having 1 to 10 carbon atoms. A monoalkyltin triamide can be reacted with an alcohol represented by the formula HOR'' in an organic solvent to form RSnOR''3 (wherein R'' is a hydrocarbyl group having 1 to 10 carbon atoms), thereby forming a product composition having a dialkyltin compound in an amount of 4 mol% or less relative to the total amount of tin.

Description

Technical Field

[0001] Cross - Reference to Related Applications This application is a continuation - in - part of U.S. Patent Application No. 15 / 950,292, filed Apr. 11, 2018, and U.S. Patent Application No. 15 / 950,286, filed Apr. 11, 2018, both entitled “Monoalkyl Tin Compounds With Low Polyalkyl Contamination, Their Compositions and Methods” (both of which are incorporated herein by reference).

[0002] The present invention relates to high - purity compositions of monoalkyltin triamides, monoalkyltin trialkoxides, or monoalkyltriamidotin and methods for producing them.

Background Art

[0003] Organometallic compounds have attracted interest for providing metal ions in a solution - processable form. Alkyltin compounds provide radiation - sensitive Sn - C bonds that can be used to pattern structures in lithography. The processing of semiconductor materials with ever - shrinking dimensions has led to a demand for materials with even broader applications to achieve the desired patterning resolution, and alkyltin compounds are promising advanced materials that offer patterning advantages.

Summary of the Invention

Means for Solving the Problems

[0004] In a first embodiment, the present invention relates to a composition comprising a monoalkyltin trialkoxide compound represented by the chemical formula RSn(OR')3 or a monoalkyltin triamide compound represented by the chemical formula RSn(NR'2)3, and a dialkyltin compound in an amount of 4 mol% or less relative to the total amount of tin, wherein R is a hydrocarbyl group having 1 to 31 carbon atoms, and R' is a hydrocarbyl group having 1 to 10 carbon atoms. A monoalkyltin triamide can be reacted with an alcohol represented by the formula HOR'' in an organic solvent to form RSnOR''3 (wherein R'' is independently a hydrocarbyl group having 1 to 10 carbon atoms), thereby forming a product composition having a dialkyltin compound in an amount of 4 mol% or less relative to the total amount of tin.

[0005] In a further embodiment, the present invention relates to a composition comprising a monoalkyltriamidotin compound represented by the chemical formula RSn-(NR'COR'')3 (wherein R is a hydrocarbyl group having 1 to 31 carbon atoms, and R' and R'' are independently hydrocarbyl groups having 1 to 10 carbon atoms).

[0006] In another embodiment, the present invention relates to a method for forming a monoalkyltin triamide compound, the method comprising the step of reacting an alkylating agent selected from the group consisting of RMgX, R2Zn, RZnNR'2, or a combination thereof with Sn(NR'2)4 in a solution containing an organic solvent, wherein R is a hydrocarbyl group having 1 to 31 carbon atoms, X is a halogen, and R' is a hydrocarbyl group having 1 to 10 carbon atoms.

[0007] In another embodiment, the present invention relates to a method for selectively forming monoalkyltin trialalkoxide compounds with low dialkyltin contamination, comprising the step of reacting RSn(NR'2)3 with an alcohol represented by the formula HOR'' in an organic solvent to form RSnOR''3, wherein the RSn(NR'2)3 reactant is a product of the method according to claim 17 having about 4 mol% or less of dialkyltin contaminants, and wherein R is a hydrocarbyl group having 1 to 31 carbon atoms, and R' and R'' are independently hydrocarbyl groups having 1 to 10 carbon atoms.

[0008] In yet another embodiment, the present invention relates to a method for forming monoalkyltriamidotin, the method comprising the steps of reacting a monoalkyltintriamide compound represented by the chemical formula RSn(NR'2)3 with an amide (R''CONHR'''') in an organic solvent, wherein R is a hydrocarbyl group having 1 to 31 carbon atoms, and R', R'' and R''' are independently hydrocarbyl groups having 1 to 8 carbon atoms, and collecting a solid product represented by the formula RSn(NR''''COR'')3.

[0009] Furthermore, the present invention relates to a method for forming a monoalkyltin trialkoxide, the method comprising the steps of reacting a monoalkyltriamidotin compound (RSn(NR'''COR'')3) with an alkali alkoxide compound (QOR', where Q is an alkali metal atom) in an organic solvent to form a product compound represented by the chemical formula RSn(OR')3, wherein R is a hydrocarbyl group having 1 to 31 carbon atoms, and R', R'' and R''' are independently hydrocarbyl groups having 1 to 10 carbon atoms.

[0010] Furthermore, the present invention relates to a method for purifying monoalkyltin trialkoxide, comprising the step of distilling a blend of monoalkyltin trialkoxide and a tetradentate non-planar complex-forming agent. [Brief explanation of the drawing]

[0011] [Figure 1] This is the 1H NMR spectrum of t-BuSn(NMe2)3 synthesized using Grignard reagents. [Figure 2] The 119Sn NMR spectrum of t-BuSn(NMe2)3 used to obtain the spectrum shown in Figure 1 is shown here. [Figure 3] This is the 1H NMR spectrum of CySn(NMe2)3 (Cy=cyclohexyl) synthesized using alkyl zinc halide reagents. [Figure 4] The 119Sn NMR spectrum of CySn(NMe2)3 is used to obtain the spectrum shown in Figure 3. [Figure 5] This is the 1H NMR spectrum of CyHpSn(NMe2)3 synthesized using a dialkylzinc reagent. [Figure 6] This is the 119Sn NMR spectrum of CyHpSn(NMe2)3 used to obtain the spectrum shown in Figure 5. [Figure 7] This is the 1H NMR spectrum of t-BuSn(NMe2)3 synthesized using Grignard reagents and a neutral base. [Figure 8] The 119Sn NMR spectrum of t-BuSn(NMe2)3 is used to obtain the spectrum shown in Figure 7. [Figure 9] This is the 1H NMR spectrum of t-BuSn(Ot-Am)3 synthesized from t-BuSn(NMe2)3. [Figure 10] The 119Sn NMR spectrum of t-BuSn(Ot-Am)3 is used to obtain the spectrum shown in Figure 9. [Figure 11] This is the structure of t-butyltris(N-methylacetamide)tin(IV) obtained by X-ray structural determination of the crystalline product. [Figure 12] This is the 1H NMR spectrum of t-butyltris(N-methylacetamide)tin(IV). [Figure 13]This is the 119Sn NMR spectrum of t-butyltris(N-methylacetamide)tin(IV). [Figure 14] This is the 1H NMR spectrum of t-BuSn(Ot-Am)3 synthesized from t-butyltris(N-methylacetamide)tin(IV). [Figure 15] This is the 119Sn NMR spectrum of t-BuSn(Ot-Am)3 synthesized from t-butyltris(N-methylacetamide)tin(IV). [Figure 16] This is the 119Sn NMR spectrum of t-BuSn(NMe2)3 with t-Bu2Sn(NMe2)2 added. The signal at 85.48 ppm corresponds to t-BuSn(NMe2)3, and the signal at 56.07 ppm corresponds to (t-Bu)2Sn(NMe2)2. [Figure 17] Figure 16 shows the 119Sn NMR spectrum of t-BuSn(NMe2)3 from the first fraction collected by fractional distillation of the sample. [Figure 18] Figure 16 shows the 119Sn NMR spectrum of t-BuSn(NMe2)3 from the second fraction collected by fractional distillation of the sample. [Figure 19] Figure 16 shows the 119Sn NMR spectrum of t-BuSn(NMe2)3 from the third fraction collected by fractional distillation of the sample. [Figure 20] This is the 119Sn NMR spectrum of baseline tBuSn(OtAm)3. [Figure 21] This is the 119Sn spectrum of tBuSn(OtAm)3 after redistillation following the addition of tris(2-aminoethyl)amine (TREN). [Modes for carrying out the invention]

[0012] Methods have been found to obtain monoalkyltin compositions, particularly monoalkyltin triamides, monoalkyltin trialalkoxides, and monoalkyltrimidosin, that produce fewer polyalkyltin by-products. In particular, three methods have been developed for the synthesis of monoalkyltin triamides with relatively few polyalkyltin by-products, which can be used immediately after synthesis or further purified. In this case, monoalkyltin trialalkoxides with correspondingly fewer polyalkyltin by-products can be synthesized using selectively synthesized monoalkyltin triamides. Furthermore, monoalkyltin triamides can be reacted in solution, regardless of their purity, to form solid monoalkyltriamide tin by removing polyalkyl by-products in the crystals. This method has been found to be effective in forming monoalkyltriamide tin with fewer polyalkyl by-products. The synthesized monoalkyltin amides and monoalkyltin alkoxides can be further purified by fractional distillation to effectively reduce polyalkyl contaminants beyond levels that may already be relatively low from direct synthesis. The level of contaminants can be determined using analytical techniques. In some embodiments, quantitative NMR (qNMR) shows that by-products can be reduced to concentrations of less than 1 mole percent. The resulting tin composition may be useful as a precursor for the synthesis of desired patterning materials. For use as a precursor for patterning materials, the reduction of polyalkyltin by-products may be beneficial for the properties of the monoalkyltin product composition for use as an EUV and UV photoresist or electron beam patterning resist.

[0013] Monoalkyltin triamides can be useful intermediate products in the preparation of organotin photoresists. Methods for preparing monoalkyltin triamides have long utilized lithium reagents to convert tin tetraamides into the desired triamides. For example, t-butyltris(diethylamide)tin (t-BuSn(NEt2)3) can be synthesized using lithium reagents according to the method described by Haenssgen, D.; Puff, H.; Beckerman, NJ Organomet. Chem. 1985, 293, 191 (incorporated in this specification by reference). However, these methods using lithium reagents can produce mixtures of monoalkyl and dialkyltin products. Furthermore, lithium contaminants may be undesirable for semiconductor applications. Reported methods for preparing monoalkyltin triamides containing secondary alkyl groups produce mixtures rich in mono-, di-, and triakyl tin products. As described below, it may be desirable to reduce all polyalkyl by-products, such as dialkyltin contaminants. While monoalkyl and dialkyl species can be separated from each other in some compounds, this separation or purification process generally increases manufacturing costs, and the accompanying dialkyl impurities may impair the performance of downstream photoresist products. Thus, it may be desirable to synthesize monoalkyltin compounds with higher purity, and if necessary, further purification by fractional distillation or other methods may reduce dialkyl or polyalkyl contamination. If the as-synthesized composition is sufficiently pure, further purification by fractional distillation can be avoided.

[0014] The use of high-purity monoalkyltin compounds, particularly mercapto compounds, as polymer stabilizers is described in U.S. Patent No. 8,198,352 to Deelman et al., entitled “High Purity Monoalkyltin Compounds and Uses Thereof,” and U.S. Patent No. 9,745,450 to Frenkel et al., entitled “Stabilizers Containing High Purity Mono-Alkyltin Compounds” (both incorporated herein by reference). These patents describe the formation of high-purity monoalkylhalides as precursors for the synthesis of stabilizer compounds. The processes described herein focus on the synthesis of high-purity monoalkyltin triamides, monoalkyltin trialkoxides, or monoalkyltriamidotin compounds using different and effective synthetic methods that may be used in conjunction with fractional distillation for purification.

[0015] The use of alkyl metal coordination compounds in high-performance radiation-based patterning compositions is described, for example, in U.S. Patent Application Publication 9,310,684 to Meyers et al., entitled “Organometallic Solution Based High Resolution Patterning Compositions,” which is incorporated herein by reference. Improvements to these organometallic compositions for patterning are described in U.S. Patent Application Publication 2016 / 0116839A1 to Meyers et al., entitled “Organometallic Solution Based High Resolution Patterning Compositions and Corresponding Methods,” and U.S. Patent Application Publication 2017 / 0102612A1 to Meyers et al., entitled “Organotin Oxide Hydroxide Patterning Compositions, Precursors, and Patterning” (hereinafter referred to as Publication '612) (both incorporated herein by reference).

[0016] Radiation patterning performed using alkyltin compositions is generally carried out using alkyltin oxo-hydroxy moieties. The compositions synthesized here can be effective precursors for forming alkyltin oxo-hydroxy compositions that are effective for high-resolution patterning. The alkyltin precursor composition is hydrolyzed with water or other suitable reagents under appropriate conditions to form a group that can form an alkyltin oxo-hydroxy patterning composition represented by the formula RSnO ,

[0018] ,

[0017] , , , x , (OH) x (where 0 < x ≦ 3). The hydrolysis and condensation reactions that can vary the composition with the hydrolysis group (X) are shown in the following reactions: RSnX3 + 3H2O → RSn(OH)3 + 3HX, RSn(OH)3 → RSnO (1.5-(x / 2)) OH x + (x / 2)H2O.

[0017] When the hydrolysis product HX is sufficiently volatile, in situ hydrolysis can be carried out using water vapor during the support coating process, but the hydrolysis reaction can also be carried out in solution to form an alkyltin oxo-hydroxy composition. These processing options are further described in Published Application No. ’612.

[0018] Polyalkyltin impurity compositions can affect condensation, leading to gas release of the photoresist during lithography, which increases the possibility of tin contamination of equipment used for thin film deposition and patterning. Based on these issues, it is highly desirable to reduce or eliminate dialkyl or other polyalkyl components. Three compositions, specifically monoalkyltin triamide, monoalkyltin trialkoxide, and monoalkyltriamidotin, are suitable for the processing described herein in order to reduce polyalkyltin contaminants in the final resist composition. As will be further described below, monoalkyltin triamide compositions can also serve as precursors for monoalkyltin trialkoxide and monoalkyltriamidotin compositions. Monoalkyltriamidotin compositions can also be convenient precursors for forming monoalkyltin trialkoxide compositions. Monoalkyltin trialkoxide compositions are readily subjected to in situ hydrolysis and condensation, and together with alcohol by-products that are generally well volatile for removal commensurate with in situ hydrolysis, they form monoalkyltin oxo-hydroxo compositions, and therefore can be desirable components in precursor patterning composition solutions.

[0019] Monoalkyltin triamide compositions with relatively low levels of polyalkyl contaminants can be directly synthesized using any one of the three methods described herein. The method using a Zn reagent was specifically developed for the synthesis of high-purity monoalkyltin triamides containing secondary alkyl groups. Furthermore, at least some of the monoalkyltin triamide compositions can be further purified using fractional distillation. The synthesis of monoalkyltriamide tin compositions from monoalkyltin triamide compositions provides further methods for reducing polyalkyl contaminants. Combining these methods can result in a further reduction of polyalkyl contaminants.

[0020] Monoalkyltin triamide compositions can generally be represented by the formula RSn(NR')3, where R and R' are independently alkyl or cycloalkyl having 1 to 31 carbon atoms, and one or more carbon atoms are optionally substituted by one of a plurality of heteroatom functional groups containing O, N, Si, and / or halogen atoms or the alkyl or cycloalkyl is further functionalized with a phenyl or cyano group. In some embodiments, R' can contain ≦10 carbon atoms and can be, for example, methyl, ethyl, propyl, isopropyl, butyl, t-butyl, isobutyl, or t-amyl. The R group can be a straight-chain, branched (i.e., secondary or tertiary at the carbon atom bonded to the metal), or cyclic hydrocarbyl group. Each R group individually and generally has 1 to 31 carbon atoms, 3 to 31 carbon atoms for groups having a secondary bonded carbon atom, and 4 to 31 carbon atoms for groups having a tertiary bonded carbon atom. In particular, branched alkyl ligands can be desirable for some patterning compositions, where the compound is R 1 R 2 R 3 CSn(NR’)3 (where R 1 and R 2 are independently alkyl groups having 1 to 10 carbon atoms and R 3 is hydrogen or an alkyl group having 1 to 10 carbon atoms) and can be represented as such. As follows, this representation of the alkyl ligand R is applicable equally to other embodiments generally having R 1 R 2 R 3 CSn(X)3 (where X corresponds to a trialkoxide or triamide moiety). In some embodiments R 1 and R 2 can form a cyclic alkyl moiety and R 3 can also be joined to other groups of the cyclic moiety. Suitable branched alkyl ligands are, for example, isopropyl (R 1 and R 2 are methyl and R 3 is hydrogen), tert-butyl (R 1 2 and R​3 ( is methyl), t-amyl (R 1 and R 2 is methyl, and R 3 (is -CH2CH3), sec-butyl (R 1 is methyl, and R 2 is -CH2CH3, and R 3 (is hydrogen), neopentyl (R 1 and R 2 is hydrogen, R 3 The cyclic group can be -C(CH3)3, cyclohexyl, cyclopentyl, cyclobutyl, and cyclopropyl. Suitable examples of cyclic groups include, for example, 1-adamantyl (-C(CH2)3(CH)3(CH2)3 or tricyclo(3.3.1.13,7)decane with a metal bond at the tertiary carbon) and 2-adamantyl (-CH(CH)2(CH2)4(CH)2(CH2) or tricyclo(3.3.1.13,7)decane with a metal bond at the secondary carbon). In other embodiments, the hydrocarbyl group may include aryl or alkenyl groups, such as benzyl or allyl, or alkynyl groups. In other embodiments, the hydrocarbyl ligand R may include any group consisting only of C and H and containing 1 to 31 carbon atoms. For example: linear or branched alkyl groups (i-Pr((CH3)2CH-), t-Bu((CH3)3C-), Me(CH3-), n-Bu(CH3CH2CH2CH2-)), cycloalkyl groups (cyclopropyl, cyclobutyl, cyclopentyl), olefin groups (alkenyl, aryl, allyl), or alkynyl groups, or combinations thereof. In further embodiments, suitable R groups may include hydrocarbyl groups substituted with heteroatom functional groups such as cyano, thio, silyl, ether, keto, ester, or halogenated groups, or combinations thereof.

[0021] Alkyl tin trialalkoxide compositions have the formula RSn(OR 0Alkyltriamidotin compositions can be represented by the formula RSn(NR''COR''')3. The R group in the formulas of alkyltin trialkoxide and alkyltriamidotin compositions may be the same R group described above for alkyltintriamide compositions, as if copying all of the corresponding considerations for these R groups above into this paragraph. Alkylamide (-NR''COR''') or alkoxide ligand -OR 0 Regarding R'', R''' and R 0 The group can independently be a hydrocarbon group having 1 to 10 carbon atoms, such as a methyl group or an ethyl group. Also, R'' and R''' can independently be hydrogen.

[0022] In some embodiments, the compositions herein (monoalkyltin triamide, monoalkyltin trialkoxide, or monoalkyltriamidotin) may contain dialkyltin contaminants in amounts of about 4 mol percent or less relative to tin, about 3 mol percent or less in a further embodiment, about 2 mol percent or less in some embodiments, about 1 mol percent or less in yet another embodiment, about 0.5 mol percent or less in other embodiments, and about 0.1 mol percent or less in yet another embodiment. Further ranges of dialkyltin contaminants within the express range described above are conceivable and will be recognized by those skilled in the art as being within the scope of this disclosure. The level of dialkyltin contaminants can generally be determined using any suitable analytical technique. In some embodiments, the amount of dialkyltin diamide or dialkyltin dialkoxide may be shown to be around or less than 0.1 mol percent by quantitative NMR. As a result of the possibility of unidentified contaminants, the quantification of monoalkyltin compositions may be measured within a few percent, but relatively small error levels of dialkyltin contaminants provide reliability using quantitative NMR as described in the following examples.

[0023] Monoalkyl Sn precursors are 1 H and 119The analysis was performed without derivatization by Sn NMR spectroscopy. Purity was quantified using the integral value from the NMR spectral peak of the monoalkyl Sn precursor relative to an internal standard. This ensured that the value accurately reflected the purity of the monoalkyl Sn precursor. A calibrated 90-degree pulse was used. 1 HNMR and reverse gate 119 Sn{ 1 The sample was irradiated for the ¹H NMR experiment. Furthermore, 1 H and 119 Sn{ 1 For both 1H NMR experiments, the T1 relaxation values ​​of the standard and analyte were measured using inversion recovery experiments. Using the measured T1 values, a recycling delay time equal to 5 times the longest T1 time of the sample was set, but it was determined that the nucleus (Z=1-e -(経過時間 / T1) ) from equilibrium (Z=1-e -5 This allows for almost complete relaxation to (=0.99326). Finally, the reduced intensity of spectral peaks not located in the center of the spectral window 119 Sn{ 1 To illustrate the 1H NMR experiment, the B1 profile of the NMR spectrometer was measured and described by centering the spectrum between the analyte and the standard. An inverted gate was used to increase the signal-to-noise ratio of the spectrum. 119 Sn{ 1 Trace Sn impurities were detected and quantified using parameters set for 1H NMR spectroscopy: the spectral center and sweep width were set to calibration values, and the sample was irradiated with a 30-degree pulse with a recycle delay time of 1 second. Linear regression analysis was used to assign quantitative values ​​to the detected low levels of Sn impurities. This method provides a 0.1% limit of quantification for dialkyl, tetrakisamide, and tetrakisalkoxide tin impurities for monoalkyltin compounds. Quantitative NMR is discussed in Weber et al., “Method development in quantitative NMR towards metrologically traceable organic certified reference materials used as 31P qNMR standards”, Anal.Bioanal.Chem., 407:3115-3123 (2015); and Pauli et al., “Importance of Purity Evaluation and the Potential of Quantitative 1 Further details are provided in "H NMR as a Purity Assay," J. Medicinal Chemistry, 57, 9220-9231 (2014) (both incorporated herein by reference).

[0024] Generally, the improved processes described herein for preparing monoalkyltin triamides include reacting a compound having an alkyl donor group, also described as an alkylating agent, with a tin tetraamide. Desired results have been achieved, where the alkylating agent may be a Grignard reagent, a diorganozinc reagent, or a monoorganozincamide. These synthesis methods allow for the direct production of monoalkyltin triamides with low polyalkyl contaminants, which can be used to form resists or further purified to further reduce contaminant levels. In the synthesis method, the alkylating agent selectively substitutes the amide group of the tin tetraamide with an alkyl group. In some embodiments, the reaction selectively produces monoalkyltin triamides with low polyalkyltin contaminants, particularly those with low dialkyltin contaminants. The described synthesis methods improve the selectivity and yield of monoalkyltin triamides by suppressing the formation of dialkyltin byproducts. The methods are particularly useful for branched alkyl systems. Subsequently, monoalkyltin triamides with low polyalkyl contaminants can be used to form monoalkyltin trialkoxides with low polyalkyl contaminants. As will be further discussed below, the formation of crystalline monoalkyltriamidotin compositions provides an alternative method to avoid polyalkyl contaminants by removing them from the crystals.

[0025] For the reaction to form a monoalkyltin triamide compound, the tintetraamide compound can be commercially available or synthesized using known techniques. For example, tetrakis(dimethylamide)tin, Sn(NMe2)4, is available from Sigma-Aldrich. For the synthesis of monoalkyltin compositions, the tintetraamide reactant in solution can generally have a concentration between about 0.025 M and about 5 M, between about 0.05 M and about 4 M in a further embodiment, or between about 0.1 M and about 2 M in yet another embodiment. Further ranges of reactant concentrations within the above express ranges are conceivable and will be recognized by those skilled in the art as being within the scope of this disclosure. Generally, the related reaction for introducing an alkyl ligand to Sn can be initiated using tintetraamide in solution in a reactor under inert gas purging and in the dark. In alternative embodiments, some or all of the tintetraamide reactants may be added in steps, in which case the concentrations in the solution to which they are added in steps may be higher, and the concentrations in the reactor may be temporary, so the above concentrations may not be directly relevant.

[0026] Alkylating agents are generally added in amounts relatively close to the stoichiometric amount. In other words, the alkylating agent is added to provide one molar equivalent of one alkyl group for one tin atom. If the alkylating agent can provide multiple alkyl groups, such as a diorganozinc compound that can provide two alkyl groups for one zinc atom, the stoichiometric amount of the alkylating agent is adjusted accordingly to provide about one alkyl group for each Sn. Therefore, a diorganozinc compound on the order of 1 mole of Zn per 2 moles of Sn is required. The amount of alkylating agent may be about ±25%, about ±20%, or about ±15% of the stoichiometric amount of the reagent, or in other words, the stoichiometric amount of the reagent + or - a selected amount to achieve the desired process performance. Further ranges of relative amounts of alkylating agents within the express range described above are conceivable and will be recognized as being within the scope of this disclosure by those skilled in the art.

[0027] Examples 2 and 3 use nearly stoichiometric amounts of alkylating agent, while Examples 1 and 4 use about 110% (i.e., 100% + 10%) of alkylating agent. The alkylating agent, dissolved in an organic solvent, can be added to the reactor stepwise, for example, dropwise or in a flow, at a rate suitable for controlling the reaction. The rate of addition can be controlled over a period of time, for example, about 1 minute to about 2 hours, and in further embodiments, about 10 minutes to about 90 minutes, to control the reaction process. The concentration of the alkylating agent in the added solution can be adjusted to a reasonable value considering the rate of addition. Essentially, the alkylating reagent can be initiated in the reactor by the stepwise addition of tin tetraamide. Further ranges of alkylating agents and addition times within the express range described above are conceivable and will be recognized as being within the scope of this disclosure by those skilled in the art.

[0028] The reaction for introducing alkyl ligands to tin atoms can be carried out in a low-oxygen, substantially oxygen-free, or anaerobic environment, and active inert gas purging can provide a suitable atmosphere, such as anhydrous nitrogen purging or argon purging. The following additives have been observed to reduce the addition of secondary alkyl groups to tin: pyridine, 2,6-lutidine, 2,4-lutidine, 4-dimethylaminopyridine, 2-dimethylaminopyridine, triphenylphosphine, tributylphosphine, trimethylphosphine, 1,2-dimethoxyethane, 1,4-dioxane, and 1,3-dioxane. Other neutral coordination bases may function similarly. The reaction may optionally further contain about 0.25 to about 4 moles of neutral coordination bases per mole of tin. The reaction may be shielded from light during the reaction. The reaction may be carried out in an organic solvent, such as an alkane (e.g., pentane or hexane), an aromatic hydrocarbon (e.g., toluene), an ether (e.g., diethyl ether, C2H5OC2H5), or a mixture thereof. The solvent may be anhydrous to avoid reaction with water. The reaction generally takes place for about 15 minutes to about 24 hours, about 30 minutes to about 18 hours in a further embodiment, and about 45 minutes to about 15 hours in yet another embodiment. The temperature during the reaction may be between about -100°C and about 100°C, between about -75°C and about 75°C in a further embodiment, and between about -60°C and about 60°C in yet another embodiment. The reaction temperature can be controlled within a desired range by using cooling or heating, and the temperature evolution during the reaction can be influenced by controlling the rate of addition of the reactants. The product monoalkyltin triamide is generally an oil that can be purified by vacuum distillation. Typical yields have been observed to be about 50 to 85 percent. Further ranges of concentrations and working conditions within the express range described above are conceivable and will be recognized as being within the scope of this disclosure by those skilled in the art.

[0029] The alkylating agent may be a Grignard reagent, a diorganozinc reagent, or a monoorganozinc amide. The Grignard reagent may be an organomagnesium halide. Specifically, the Grignard reagent in the described reaction may be RMgX (wherein X is a halide, generally Cl, Br, or I). R may be alkyl or cycloalkyl, having 1 to 31 carbon atoms, and generally R may be more fully described above with respect to the R portion of the product composition, as if the whole were incorporated for this consideration. For example, the alkyl or cycloalkyl may be branched, may contain an aromatic group, and / or may have one or more heteroatomic functional groups containing atoms such as O, N, Si, and / or halogens. Grignard reagents are commercially available or can be synthesized using known methods. Commercial sources include American Elements Company, Sigma-Aldrich, and many other suppliers.

[0030] In some embodiments, the alkylating agent is a diorganozinc reagent. The diorganozinc reagent can donate two alkyl groups to tin, and therefore the amount of diorganozinc reagent is adjusted for differences in molar equivalents. Specifically, the diorganozinc reagent may be R2Zn, where R is an alkyl or cycloalkyl group having 1 to 31 carbon atoms. The R group can be more completely defined as described above for the R portion of the product composition, and the above considerations regarding the R group in relation to the product monoalkyltin compound are considered part of this consideration, as reproduced here. For example, the alkyl or cycloalkyl group may be branched and may have one or more heteroatom functional groups containing atoms such as O, N, Si, and / or halogens. (e.g., dicycloheptylzinc((C7H)) 13 The 2Zn) reactants are exemplified below. Diorganozinc compounds are commercially available or can be synthesized using known techniques. Commercial sources include, for example, Alfa Aesar, Sigma-Aldrich, Rieke Metals (Nebraska, USA) and Triveni Chemicals (India). The reactants of the examples were synthesized.

[0031] In further embodiments, the alkylating agent is a monoorganozincamide (RZnNR'2). R can be an alkyl or cycloalkyl group, generally having 1 to 30 carbon atoms. The R group can be more completely defined as described above with respect to the R portion of the product composition, and the above considerations regarding the R group in relation to the product monoalkyltin compound are considered to be part of this consideration, as reproduced here. For example, alkyl or cycloalkyl groups can be branched and may have one or more carbon atoms substituted with one or more heteroatom functional groups containing atoms such as O, N, Si, and / or halogens. In some embodiments, R' is an alkyl or cycloalkyl group, which may be substituted with heteroatoms. In some embodiments, R' may have 1 to 8 carbon atoms, in some embodiments 1 to 5 carbon atoms, and in yet another embodiment 1 to 3 carbon atoms. R' may be a methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, or t-amyl group. Monoorganozincamides can be synthesized, for example, from alkylzinc halides (RZnX, X=I, Br, Cl) and lithium amides (LiNR'2), which are commercially available reagents from Sigma-Aldrich.

[0032] Monoalkyltintriamides produced by the methods described above or by other methods not explicitly stated herein may be further purified by fractional distillation. To reduce the temperature of the distillation process, the pressure may be reduced, for example, to about 0.01 Tor to about 10 Tor, in a further embodiment to about 0.05 Tor to about 5 Tor, and in a further embodiment to about 0.1 Tor to about 2 Tor. Suitable fractional distillation columns with a suitable volume for the process can be used, and these are commercially available. The desired separation can be achieved by controlling the temperature in the container holding the material to be purified and along the column. Thermal conditions for one embodiment are shown in Example 8 below, and these conditions can be readily generalized for other compositions based on the teachings herein. If the dialkyltintriamide contaminant has a higher boiling point than the monoalkyltintriamide, the monoalkyltintriamide may be separated and removed during the distillation process. Although fractions may be taken together with the large amount of liquid removed during the fractional distillation stages, Example 8 shows good separation in a moderate yield without detectable contaminants. If the dialkylsutriamid contaminant has a lower boiling point than the monoalkylsutriamid, the dialkylsutriamid can be separated and removed by collecting and discarding the initial fraction during the distillation process.

[0033] Monoalkyltin trialalkoxides can be prepared by reacting the corresponding monoalkyltin triamide with an alcohol and a base in a non-aqueous solvent. Using the processing described herein, a small amount of polyalkyltin contaminants in the monoalkyltin triamide can be transferred to the product monoalkyltin trialalkoxide, resulting in the product monoalkyltin trialalkoxide having essentially the aforementioned molar percentage of low dialkyltin contaminants. Suitable organic solvents include, for example, alkanes (e.g., pentane or hexane), aromatic hydrocarbons (e.g., toluene), ethers (e.g., diethyl ether, C2H5OC2H5), or mixtures thereof. The alcohol is selected to provide the desired alkoxide group, such that the alcohol ROH introduces the -OR group as a ligand bonded to tin. Suitable R group candidates are provided above, correspondingly indicating the alcohol. An example using t-amyl alcohol is given below, but other alcohols can be used similarly to provide the desired -OR alkoxide ligand. The alcohol can be provided in nearly stoichiometric quantities. Since three amide groups are substituted with alcohol, 3 molar equivalents of alcohol is the stoichiometric amount. Generally, the amount of alcohol can be at least about -5% of the stoichiometric equivalent and, in further embodiments, at least approximately the stoichiometric equivalent, and a large excess of alcohol can be used. Example 5 is carried out using alcohol at more than +3.33% of the stoichiometric equivalent, i.e., 3.1 moles of alcohol per mole of mono-alkyltintriamide.

[0034] To facilitate the purification of the alkyltin trialkoxide product, tetradentate chelating agents can be added to coordinate unreacted tin tetraamide species, forming a complex that does not vaporize during distillation. For example, TREN, triethylenetetraamine (trien), or other tertadentate non-planar coordinating ligands can be used to complex with unreacted species and promote purification. The coordinating ligand may be added at a time of selection from the start of the reaction until any time before distillation, in an amount of about 0.5 mol% to about 15 mol%, and in further embodiments, about 1.0 mol% to about 10 mol%, relative to the molar amount of tin. Tetradentate non-planar coordinating ligands such as TREN have also been found to be effective in complexing with tin tetraalkoxide compounds to suppress their distillation. In general, it is desirable to have at least a nearly stoichiometric amount of tetradentate chelating agent to prevent each tin tetraamide from distilling. Thus, the amount of tetravalent complexing agent relative to a given amount of tetraamide may be about 1:1 molar ratio, or in some embodiments, at least about 95 mol percent of tetravalent complexing agent per mole of tintetraamide, in further embodiments about 98 mol percent to about 200 mol percent, and in yet another embodiment about 99 mol percent to about 120 mol percent. Thus, tetradentate non-planar coordinating ligands may be effective in improving the purification of monoalkyl tin trialkides from either tetraamide or tetraalkoxide tin compounds. Further ranges of reactant amounts within the express range described above are conceivable and will be recognized by those skilled in the art as being within the scope of this disclosure. If necessary, fractional distillation may be performed to further purify monoalkyl tin trialkides from polyalkyl contaminants.

[0035] While monoalkyltin triamides with low polyalkyl contaminants can be effectively used to form derivatives with correspondingly low polyalkyl contaminants, the synthesis of monoalkyltriamidotin from monoalkyltin triamides can also form products with low contaminant content, even if the contaminant level of the monoalkyltin triamide is not low. This is due to the crystal formation of monoalkyltriamidotin, which can clearly remove polyalkyl contaminants. Thus, the synthesis of monoalkyltriamidotin provides an auxiliary or alternative route for forming compositions with low dialkyltin contaminants. For this reason, in some embodiments, monoalkyltin triamides with higher contaminant content can be used from commercial sources or reaction routes with higher contaminant levels, while still obtaining product compositions with low dialkyltin contaminants. Monoalkyltriamidotin compounds can be used to form monoalkyltin trialkoxide compositions with low dialkyltin contaminants.

[0036] The reaction requires the addition of an N-alkylamide, such as N-methylacetamide (CH3CONHCH3), to a monoalkyltin triamide. Generally, the N-alkylamide reactant is R a CONHR b (In the formula, R a and R b The group can be independently described as a hydrocarbon group having 1 to 10 carbon atoms, such as a methyl group, ethyl group, propyl group, or isopropyl group. The crystalline structure of the product compound has been confirmed, and the structure is shown in the following examples. In summary, the amide group in the product is bonded to tin at the nitrogen atom, forming the corresponding ligand structure.

[0037] To control the heat generation and progress of the reaction, the N-alkylamide reactant can be added stepwise, for example, over a period of at least about 2 minutes. The monoalkyltin triamide can be dissolved in an organic solvent at concentrations of about 0.1 M to about 8 M and, in further embodiments, about 0.2 M to about 6 M. Suitable organic solvents include, for example, alkanes (e.g., pentane or hexane), aromatic hydrocarbons (e.g., toluene), ethers (e.g., diethyl ether, C2H5OC2H5), or mixtures thereof. The reaction is exothermic, and generally no additional heat is required. The reaction product may form crystals, and the reaction can generally continue for about 20 minutes to 24 hours. After the reaction is complete, the solvent can be removed and the product crystals can be collected. The crystals can be washed and dried. It can be observed that the dialkyltin compound is removed from the product crystals. Further ranges of reactant concentrations, addition times, and reaction times within the express range described above are conceivable and will be recognized as being within the scope of this disclosure by those skilled in the art.

[0038] For processing radiosensitive resist compositions, it may be desirable to react monoalkyltriamidotin to form monoalkyltin trialkoxide compounds. Alkali alkoxides can be used to substitute the triamide ligand with the alkoxide ligand by reaction in an organic slurry. When the monoalkyltin trialkoxide compound is formed, it dissolves in organic solvents at concentrations of about 0.01 M to 2 M and, in further embodiments, about 0.04 M to about 1 M. Alkali alkoxide compounds can be denoted as ZOR' (wherein Z is an alkali atom such as K, Na, or Li, and -OR' is an alkoxide group that provides the corresponding R' group for RSn(OR')3 product compositions). Several alkali alkoxides are commercially available, for example, from Sigma-Aldrich, and these compounds are highly hygroscopic, so they can be isolated from air. Suitable organic solvents include, for example, alkanes (e.g., pentane or hexane), aromatic hydrocarbons (e.g., toluene), ethers (e.g., diethyl ether, C2H5OC2H5), or mixtures thereof. Alkali alkoxides can be provided in at least stoichiometric amounts, corresponding to three alkoxide groups per tin atom. The reaction can be carried out for about 15 minutes to about 48 hours. The product liquid can be purified by distillation. Further ranges of concentrations and times within the express range described above are conceivable and will be understood by those skilled in the art to be within the scope of this disclosure. [Examples]

[0039] Example 1: t-BuSn(NMe 2 ) 3 synthesis This example aims to synthesize a tin compound having a t-butyl group bonded to tin substituted with an N-methylamide group.

[0040] In an argon-filled glove box, Sn(NMe2)4 (827.5 g, 2805 mmol, Sigma) was placed in a 5 L three-neck round-bottom flask. Anhydrous ether (2000 mL) was added to the flask. A large amount of t-BuMgCl (1500 mL, 2.06 M (freshly titrated), 3090 mmol) was added to a separate 2 L two-neck round-bottom flask. The flasks were stoppered and attached to a Schlenkline. The Sn(NMe2)4 solution was transferred to a 5 L jacketed reactor and stirred at 240 RPM. Using an automatic syringe pump, 50 ml min of t-BuMgCl solution was added to the 5 L jacketed reactor. -1 The mixture was supplied at a rate of . The temperature of the mixture in the jacketed reactor was maintained at 20°C. After the t-BuMgCl solution was completely added, the reaction mixture was stirred overnight. The resulting mixture was transferred through a 10 L filter reactor to a 5 L three-neck round-bottom flask equipped with a stirring bar. The solids in the 5 L jacketed reactor and filter reactor were washed with pentane (2 × 1 L). The washes were collected in a 5 L three-neck round-bottom flask equipped with a stirring bar, and volatiles were removed under vacuum. After removal of volatiles, a pale yellow oily suspension corresponding to the crude product was observed. The flask was placed in a glove box, and the crude product was filtered through a coarse porous frit funnel. The filtrate was transferred to a 2 L two-neck round-bottom flask equipped with a stirring bar, which was stoppered and transferred to a Schlenklein. The crude product was purified by short-pass vacuum distillation in a 1 L receiving flask (500 mlitol, 65°C-75°C) to yield 323-604 g of colorless oil identified as t-BuSn(NMe2)3, with a concentration of 37-70%. Proton NMR (Figure 1) and 119 Sn NMR (Figure 2) is performed to characterize the product from which the following peaks are observed: 1 H NMR(C6D6,MHz):2.84(s,18H,-NCH3),1.24(s,9H,H3CC-); 119 Sn NMR (C6D6, 186.4MHz: -85.69). Quantitative proton NMR and tin NMR were performed to measure the purity of the product. Base dona standard. qNMR: 1 H, standard 1,3,5-trimethoxybenzene, purity 94.5(3) mol% (94.5 ± 0.3 mol%) monoalkyltin;119 Sn, standard MeSnPh3, purity 93.5(2) mol% monoalkyltin.

[0041] [Table 1]

[0042] Example 2: CySn(NMe 2 ) 3 Synthesis of (Cy = cyclohexyl) This example aims to synthesize tin compounds having a cyclohexyl group from a Zn reagent that substitutes the N-methylamide group of Sn(NMe2)4.

[0043] Sn(NMe2)4 (5.61 g, 19.0 mmol, Sigma) was placed in a 250 mL three-neck round-bottom flask (RBF) in an argon-filled glove box. Anhydrous ether (150 mL) was added to the flask. Separately, w / LiNMe2 (0.97 g, 19.0 mmol, Sigma) and anhydrous ether (20 mL) were placed in 100 mL of RBF. CyZnBr (Cy=cyclohexyl, 48.5 mL, 0.392 M, 19.0 mmol, Sigma) was slowly added to this flask to produce CyZnNMe2. Since the reaction is exothermic, the reaction temperature was controlled by slowly adding CyZnBr. A dropping funnel and reflux condenser were attached to the 250 mL three-neck RBF on a Schlenkle line under activated argon purging. 250 mL of RBF was covered with aluminum foil to prevent light from entering, and the CyZnNMe2 solution was added to a dropping funnel and dispensed dropwise while stirring. After complete addition, the reaction mixture was stirred overnight, and the solvent was removed under vacuum to produce a pale orange oil along with the precipitate. The oil was purified by vacuum distillation (58-62°C, 150 millitol). The obtained product was 4.38 g (69% yield) of colorless oil identified as CySn(NMe2)3. Proton NMR (Figure 3) and 119 Sn NMR (Figure 4) characterizes the product by showing the following peaks: 1H NMR(C6D6,500MHz):2.85(s,18H,-NCH3),1.86(m,3H,-CyH),1.69(m,2H,-CyH),1.53(m,3H,-CyH),1.24(m,3H,-CyH); 119 Sn NMR (C6D6, 186.4MHz): -73.77.

[0044] Example 3. (CyHp)Sn(NMe 2 ) 3 Synthesis of (CyHp = cycloheptyl) This example aims to synthesize a tin triamide having a cycloheptyl group, as shown in the following formula. In this synthesis, the cycloheptyl group from the zinc reagent (CyHp)2Zn substitutes for the N-methylamide group of Sn(NMe2)4. [ka]

[0045] Sn(NMe2)4 (6.49 g, 22.0 mmol, Sigma) was placed in a 250 mL three-neck round-bottom flask (RBF) in an argon-filled glove box. Anhydrous ether (150 mL) was added. A dropping funnel and reflux condenser were attached to the 250 mL three-neck RBF on a Schlenkle line under activated argon purging. (CyHp)2Zn (0.351 M, 31.3 mL, 11.0 mmol), prepared separately, was synthesized as follows: 2CyHpMgBr + Zn(OCH3)2. The (CyHp)2Zn solution was added to the dropping funnel under activated argon purging while the 250 mL RBF was covered with aluminum foil to block out light, and then dispensed dropwise with stirring. After complete addition, the reaction mixture was stirred overnight. Next, the solvent was removed under vacuum. The reaction flask was placed in a glove box and hexane was added. The solution was filtered over Celite®, and the solvent was removed under vacuum to yield a colorless oil along with the precipitate. The oil was purified by vacuum distillation (82-86°C, 180 millitol). The resulting product was 4.01 g (52% yield) of colorless oil identified as (CyHp)Sn(NMe2)3. Proton NMR (Figure 5) and 119Sn NMR (Figure 6) characterizes the product by showing the following peaks: 1 H NMR(C6D6,500MHz):2.84(s,18H,-NCH3),2.01(m,2H,-CyHpH),1.82(m,1H,-CyHpH),1.69-1.23(m,10H,-CyHpH); 119 Sn NMR (C6D6, 186.4MHz): -66.93.

[0046] Example 4. t-BuSn(NMe) using an additional base 2 ) 3 Preparation This example demonstrates the synthesis of a tin composition by the reaction of a Grignard reagent with Sn(NMe2)4 in the presence of a base. [ka]

[0047] Sn(NMe2)4 (539.0 g, 1.827 mol, Sigma) was placed in a 5 L three-neck RBF in an argon-filled glove box. Approximately 3 L of anhydrous diethyl ether and pyridine (289.1 g, 3.66 mol) were added to the flask. The two necks of the flask were stoppered with glass stoppers, and a vacuum adapter was attached to the third neck. Separately, 1 L of t-BuMgCl (Grignard reagent), measured in a volumetric flask (2.01 M (titrated), 2.01 mol, Sigma), was placed in a 2 L two-neck RBF. A 5 L jacketed Chemglass (trademark) reactor was prepared on an argon-filled Schlenkline for high vacuum and thermal reaction. Argon was returned to the reactor, and then the jacket around the reactor vessel was cooled to -30°C.

[0048] The contents of a 5 L three-neck RBF were transferred to a Chemiglass (trademark) reactor through a polyethylene (PE) tube under positive argon pressure. Stirring was started using an overhead stirrer, and the reaction temperature was cooled to -15°C. On a Schlenkline, the Grignard reagent was added through a polyethylene (PE) tube over 20-30 minutes under positive argon pressure, while maintaining the internal reaction temperature below 5°C. A deep orange color and precipitate formed. After complete addition, the reaction mixture was stirred overnight, shielded from light with aluminum foil, to reach room temperature.

[0049] After a nightly reaction, the reaction color was pale yellow. The solvent was removed under vacuum with the assistance of a heating jacket at 30-35°C. After solvent removal, anhydrous pentane (approximately 2.5 L) was added to the reactor by polyethylene tube under positive argon pressure, and the solids were thoroughly mixed using an overhead stirrer. The reaction product dispersed in the pentane was transferred to a 10 L filter reactor by polyethylene tube under positive argon pressure. The reaction product was filtered and then transferred to 3 L of RBF through polyethylene tube. The pentane solvent was removed under vacuum from the resulting pale yellow filtrate, leaving a yellow oil. The oil was transferred to a 1 L Schlenk flask and vacuum distilled using a short-pass distillation head (50-52°C, 300 mlitol) to produce 349.9 g (62%) of colorless oil. Figure 7 1 (HNMR) and Figure 8 ( 119 The Sn NMR spectrum is similar to that shown in Figures 1 and 2, indicating that the product consists of monoalkyl species in equilibrium with Sn(NMe2)4. The purity of the product was measured by quantitative proton NMR and tin NMR using selected standards. qNMR: 1 H, standard 1,3,5-trimethoxybenzene, purity 89.9(7) mol% monoalkyltin; 119 Sn, standard MeSnPh3, purity 93.6(4) mol% monoalkyltin.

[0050] [Table 2]

[0051] Example 5. t-BuSn(NMe 2 ) 3 High-purity monoalkyl alkoxide t-Bu Preparation of Sn(OtAm)3 This example demonstrates the synthesis of monoalkyltin trialalkoxides from corresponding monoalkyltin triamides by the following reaction. [ka]

[0052] In a glove box, approximately 500 mL of pentane and t-BuSn(NMe2)3 (329.4 g, 1.07 mol) from Example 4 were added to a 2 L two-neck RBF. The flask was tare-added on a balance, and tris(2-aminoethyl)amine (3.91 g, 26.7 mmol) was added directly to the reaction mixture by syringe. During the reaction and purification, the amine complexed and removed the tintetrakisamide. If it is not necessary to remove the tintetrakisamide from the system, the product of Example 1 can be used to synthesize additional monoalkyltin products. The reaction sequence can be continued using the materials synthesized according to Example 1. A magnetic stirring bar was added, then the reaction was sealed and brought to a Schlenklein. The flask was cooled in a dry ice / isopropanol bath. Separately, tert-amyl alcohol (2-methyl-2-butanol) (292.2 g, 3.315 mol) and a small amount of pentane were placed in a 1 L Schlenk flask and then attached to a Schlenk line. The alcohol / pentane solution in the Schlenk flask was transferred by cannula to a reaction flask with an outlet purge to a mineral oil bubbler, which was inline connected to an acid trap solution for degassed NMe2H. After the alcohol had been completely added, the reaction was allowed to reach room temperature and stirred for 1 hour. After 1 hour of reaction, the solvent was removed under vacuum, and the product was vacuum distilled (95-97°C, 500 mlitol) to yield 435 g (93%) of colorless oil. Figure 9 1 (HNMR) and Figure 10 ( 119 The following NMR spectrum of the final product t-BuSn(Ot-Am)3 is observed (Sn NMR): 1H NMR(C6D6,500MHz):1.61(m,6H,-OC(CH3)2CH2),1.37(m,18H,-OC(CH3)2),1.28(s,9H,-C(CH3)3),1.01(m,9H,-OC(CH3)2CH2CH 3 ); 119 Sn NMR (C6D6, 186.4MHz): -240.70. Quantitative proton NMR was performed to measure the purity level of the product. qNMR: 1 H, standard 1,3,5-trimethoxybenzene, purity 97.7(3%); 119 Sn, standard MeSnPh3, 99(1)mol% monoalkyltin.

[0053] Example 6. Preparation of t-butyltris(N-methylacetamide)tin(IV) This example demonstrates the synthesis of a monoalkyltriamidotin composition by the reaction of t-BuSn(NMe2)3 with N-methylacetamide. [ka]

[0054] In a glove box, t-BuSn(NMe2)3 (40.13 g, 130 mmol) containing 1% t-Bu2Sn(NMe2)2 was placed in a 250 mL Schlenk round-bottom flask. t-BuSn(NMe2)3 was synthesized according to Example 1 or Example 4. 50 ml of toluene was added to the round-bottom flask, and then N-methylacetamide (28.6 g, 391 mmol, Sigma) was slowly added to control heat generation. All N-methylacetamide was washed in the reaction flask using an additional 30 mL of toluene. The flask was sealed with a ground glass stopper and transferred to a Schlenk line. Over several hours, large crystals precipitated from the solution. Toluene was removed by cannula under activated argon purging. The white crystals were removed, washed twice with 100 mL of pentane using a cannula, and then removed. They were dried in vacuum, yielding 40.6 g (80%) of t-butyltris(N-methylacetamide)tin(IV). Figure 11 shows the crystal structure of the solid as confirmed by X-ray diffraction. As shown in Figure 12, the proton NMR spectrum yields the following peaks: 1 ¹H NMR (C6D6, 500MHz): 2.52(s,9H,-NCH3), 2.01(m,2H,-CyHpH), 1.74(s,9H,-(H3C)3CSn), 1.69(s,9H,-CH3CO). As shown in Figure 13, the tin NMR spectrum yields the following peaks: 119 Sn NMR (C6D6, 186.4MHz):-346.5.

[0055] Example 7. t-BuSn(Ot-Am) 3 synthesis This example demonstrates the synthesis of t-BuSn(Ot-Am)3 from the t-butyltris(N-methylacetamide)tin(IV) product of Example 6.

[0056] In a glove box under an argon atmosphere, t-butyltris(N-methylacetamide)tin(IV) (100 g, 255 mmol) from Example 6 was placed in a 3 L round-bottom flask, followed by the addition of NaOtAm (98 g, 890 mmol, Sigma). The mixture was slurryed in 1.5 L of pentane using an electromagnetic stirrer and a 2.5-inch oval stirring bar. The slurry concentrated and became milky white after 30–60 minutes. Stirring was continued for approximately 16 hours. The slurry was then filtered through a porous frit funnel in the glove box, and the recovered solids were washed twice with 100 mL of pentane. The retained solids formed a very fine cake during filtration, so stirring was used occasionally to facilitate recovery.

[0057] The filtrate was transferred to a two-necked 2L flask equipped with a stirring bar, and the flask was then sealed with a ground-glass stopper and a Schlenk inlet adapter. The flask was removed from the glove box and connected to a vacuum line in a fume hood to remove excess solvent under vacuum. The crude product was then purified by vacuum distillation and collected in a 100 mL Schlenk storage flask. For vacuum distillation, the oil bath was set to 150°C. The product was distilled at 300 millitol and a temperature of 98–102°C to yield 74 g (66%) of the product. As shown in Figure 14, the proton NMR spectrum showed the following shifts: 1 ¹H NMR shift [400MHz, C6D6]: 1.64(q,6H,-CH2), 1.39(s,18H,-C(CH3)2), 1.29(s,9H,(CH3)3CSn), 1.03(t,9H,-CCH3). As shown in Figure 15, 119 The Sn NMR spectrum showed the following peaks: 119 Sn NMR shift [149.18 MHz, C6D6]: -241.9. Quantitative NMR was performed to determine purity following standard evaluation. 1 HqNMR, standard 1,3,5-trimethoxybenzene, purity 97.3(1) mol% monoalkyl.

[0058] [Table 3]

[0059] Example 8. Fractional distillation and purification This example demonstrates the effectiveness of fractional distillation for purifying t-BuSn(NMe2)3 by separating it from a mixture of t-Bu2Sn(NMe2)2 and t-BuSn(NMe2)3.

[0060] In a glove box, t-BuSn(NMe2)3 (total 1420 g, 4.6 mol) containing approximately 3.27% t-Bu2Sn(NMe2)2 was placed in a 3000 mL three-neck round-bottom flask (RBF); the sample was prepared using the modified t-BuMgCl:Sn(NMe2)4 ratio as described in Example 1. Glass stoppers were placed on two necks of the RBF, and the third neck was attached to a Schlenkline. Separately, a 5 L Chemiglass jacketed reactor was fitted with an overhead stirrer, a temperature probe, and two 18-inch distillation columns stacked vertically. The distillation columns were Pro-Pak® (ThermoScientific, 0.24 in) 2 The column was packed with high-efficiency distillation column packing. A short-pass distillation head with a temperature probe was attached to the top of the distillation column. Next, the top of the short-pass head was connected to a three-arm cow joint holding three 500 mL Schlenk-type flasks (Schlenk bombs). The reactor was degassed and refilled three times with argon. The t-Bu2-rich mixture was added to the reactor under argon using a large cannula. The jacketed reactor was heated under reduced pressure (500 ml) between 110 and 120°C to start distillation. The temperature at the bottom of the distillation column was measured at 95 to 100°C, while the temperature at the top of the column was maintained between 58 and 60°C. Three fractions were collected, and each 119 Analysis was performed by Sn NMR spectroscopy. Figures 16-19 show the pooled sample (Figure 16) and each of the three fractions (Figures 17-19, in order). 119 This is a plot of the Sn NMR spectra. None of the three fractions showed an NMR signal for t-Bu2Sn(NMe2)2. The total yield when all fractions were combined was 850 g (60%).119 Sn NMR (C6D6, 186.4 MHz): -85.45

[0061] Example 9. Vacuum distillation purification This example demonstrates the effectiveness of vacuum distillation to purify t-BuSn(OtAm)3 to produce a composition free of amides, as demonstrated by its separation from a mixture of Sn(OtAm)4 and t-BuSn(OtAm)3. Tris(2-aminoethyl)amine (TREN) was used as a purification aid.

[0062] In a glove box with an argon atmosphere, a 100 mL round bottom Schlenk flask was charged with t-BuSn(OtAm)3 [25 g, 55.825 mmol] contaminated with approximately 1.3% Sn(OtAm)4, followed by 10 mL of anhydrous pentane. The mixture was stirred using a magnetic stirrer before adding TREN [0.112 g, 0.7686 mmol] using a glass Pasteur pipette. The flask was sealed using a glass stopper for the 24 / 40 ST joint and a Teflon® valve for the side arm port. The flask was connected to a Schlenk line, placed under an inert gas (nitrogen), and placed in a silicone oil bath. Stirring and heating control were achieved using a Heidolph HEI-TEC stirring plate with a Pt / 1000 temperature probe, allowing feedback temperature control for the oil bath. The bath was held at 45 °C before removing the excess solvent under vacuum. When verifying solvent removal using a millitorr vacuum gauge, a short path vacuum distillation apparatus was set up using a 50 mL Schlenk-type flask as the receiving vessel. The vacuum distillation was carried out at an absolute pressure of 300 millitorr, a bath temperature of 150 °C, and a vapor temperature in the range of 94 - 98 °C.

[0063] Sn(O t The theoretical recovery assuming 100% removal of Sn(OAm)4 is 24.66 g, and the recovered distillate was 21.70 g, resulting in an 88% recovery. 119 The Sn NMR spectra are shown in Figures 20 (baseline) and 21 (purified). 119Sn NMR shift [149.18 MHz, C6D6]: t Bu2Sn(O t Am) 2: -113 ppm; t BuSn(O t Am)3:-241ppm;Sn(O t Am) 4: -370 ppm.

[0064] The embodiments described above are illustrative and not limiting. Further embodiments are within the scope of the claims. Furthermore, although the present invention has been described with reference to specific embodiments, those skilled in the art will recognize that modifications can be made in form and detail without departing from the spirit and scope of the invention. Any incorporation by reference to the above documents is limited so as not to incorporate subject matter contrary to the express disclosure herein. To the extent that a particular structure, composition and / or process is described herein with respect to components, elements, components or other divisions, it should be understood that the disclosure herein extends, unless otherwise specified, to specific embodiments, embodiments including specific components, elements, components, other divisions or combinations thereof, which may include additional features that do not alter the fundamental nature of the subject matter as suggested in the discussion, and embodiments which are essentially derived from such specific components, components or other divisions or combinations thereof.

Claims

1. Chemical formula RSn(OR') ３ Monoalkyl tin trialkoxide compounds represented by or with the chemical formula RSn(NR') ２ ) ３ A monoalkyl tin triamide compound represented by, A composition comprising a dialkyltin compound in an amount of 4 mol% or less relative to the total amount of tin, wherein the formula is: R is a hydrocarbyl group having 1 to 31 carbon atoms, and A composition in which R' is a hydrocarbyl group having 1 to 10 carbon atoms.

2. R is R １ R ２ R ３ C- (wherein R １ and R ２ are each independently an alkyl group having 1 to 10 carbon atoms, and R ３ is hydrogen or an alkyl group having 1 to 10 carbon atoms), which is a branched alkyl ligand represented by the formula, The composition according to claim 1.

3. R is methyl (CH ３ -), ethyl (CH ３ CH ２ -), isopropyl (CH ３ CH ３ HC-), t-butyl((CH ３ ) ３ C-), tert-amil (CH ３ CH ２ (CH ３ ) ２ C-), sec-butyl (CH ３ (CH ３ CH ２ )CH-), Neopentyl (CH ３ ) ３ CCH ２ The composition according to claim 1, comprising -), cyclohexyl, cyclopentyl, cyclobutyl, or cyclopropyl.

4. The composition according to any one of claims 1 to 3, wherein R' comprises a methyl group, an ethyl group, an isopropyl group, or a t-butyl group.

5. The composition according to any one of claims 1 to 3, wherein R' contains a t-amyl group.

6. A composition according to any one of claims 1 to 5, comprising about 1 mol% or less of a dialkyltin compound.

7. A composition according to any one of claims 1 to 6, comprising a monoalkyl tin triamide.

8. A solution comprising the composition according to claim 1 or any one of claims 4 to 7 and an organic solvent.

9. A solution according to claim 8 having a concentration of approximately 0.005 M to approximately 0.5 M, wherein the solvent contains an alcohol.

10. R is methyl (CH ３ -), ethyl (CH ３ CH ２ -), isopropyl (CH ３ CH ３ HC-), t-butyl((CH ３ ) ３ C-), tert-amil (CH ３ CH ３ (CH ３ ) ２ C-), sec-butyl (CH ３ (CH ３ CH ２ )CH-), Neopentyl (CH ３ ) ３ CCH ２ The solution according to claim 8 or 9, comprising -), cyclohexyl, cyclopentyl, cyclobutyl, or cyclopropyl, wherein R' comprises a methyl group, an ethyl group, an isopropyl group, a t-butyl group, or a t-amyl group.

11. A method for selectively forming monoalkyltin trialalkoxide compounds with low dialkyltin contamination, The composition according to claim 7 is reacted with an alcohol represented by the formula HOR'' in an organic solvent to obtain RSnOR'' ３ A method comprising the step of forming a product composition having a dialkyltin compound in an amount of 4 mol% or less relative to the total amount of tin, by forming a hydrocarbyl group having 1 to 10 carbon atoms (wherein R'' is independently).

12. Chemical formula RSn-(NR'COR'') ３ (wherein R is a hydrocarbyl group having 1 to 31 carbon atoms, and A composition comprising a monoalkyltriamidotin compound represented by a hydrocarbyl group having 1 to 10 carbon atoms, where R' and R'' are independently represented by such groups.

13. The composition according to claim 12, wherein R' is a methyl group.

14. The composition according to claim 12 or claim 13, wherein R'' is a methyl group.

15. R is methyl (CH ３ -), ethyl (CH ３ CH ２ -), isopropyl (CH ３ CH ３ HC-), t-butyl((CH ３ ) ３ C-), t-amyl (CH ３ CH ３ (CH ３ CH ２ )C-),sec-butyl(CH ３ (CH ３ CH ２ )HC-), Neopentyl (CH ３ ) ３ CCH ２ The composition according to claim 12, comprising -), cyclohexyl, cyclopentyl, cyclobutyl, or cyclopropyl.

16. The composition according to any one of claims 12 to 15, which is crystalline and contains about 1 mole percent or less of dialkyltin contaminants.

17. RMgX, R ２ Zn, RZnNR' ２ An alkylating agent selected from the group consisting of , or a combination thereof, is dissolved in an organic solvent in a solution containing Sn(NR' ２ ) ４ This is a process of causing a reaction, In the formula, R is a hydrocarbyl group having 1 to 31 carbon atoms. X is a halogen, and A method for forming a monoalkyltintriamide compound, comprising the step of R' being a hydrocarbyl group having 1 to 10 carbon atoms.

18. The method according to claim 17, wherein the solution has a tin concentration between approximately 0.01 M and approximately 5 M.

19. The method according to claim 17 or claim 18, wherein the organic solvent comprises an alkane, an aromatic hydrocarbon, an ether, or a mixture thereof.

20. The method according to any one of claims 17 to 19, wherein the solution has an alkylating agent concentration of about ±25% relative to the stoichiometric reaction of the tin reagent and the alkylating agent.

21. The method according to any one of claims 17 to 20, wherein the reaction is carried out in an inert atmosphere by stepwise addition of the alkylating agent while shielded from ambient light.

22. The method according to any one of claims 17 to 21, wherein the alkylating agent is added in stages over a period of 10 to 90 minutes.

23. The method according to any one of claims 17 to 21, wherein the reaction is carried out at a temperature of -100°C to 100°C over a period of 15 minutes to 24 hours.

24. The method according to any one of claims 17 to 23, wherein the solution further comprises 0.25 to 4 molar equivalents of a neutral coordination base relative to tin.

25. RSn(NR') ２ ) ３ The alcohol represented by the formula HOR'' is reacted with an organic solvent to form RSnOR'' ３ A process for forming RSn(NR' ２ ) ３ A method for selectively forming a monoalkyltin trialkoxide compound with low dialkyltin contamination, comprising the step of a step in which the reactant has about 4 mol% or less of dialkyltin contaminants and is a product of the method according to claim 1, wherein R is a hydrocarbyl group having 1 to 31 carbon atoms, and R' and R'' are independently hydrocarbyl groups having 1 to 10 carbon atoms.

26. The method according to claim 25, wherein the reaction is carried out using an amount of tetradentate chelating agent in an amount of about 0.5 mol% to about 15 mol% relative to the molar amount of tin.

27. Chemical formula RSn(NR' ２ ) ３ A step of reacting a monoalkyl tin triamide compound represented by with an amide (R''CONHR'''') in an organic solvent, wherein R is a hydrocarbyl group having 1 to 31 carbon atoms, and R', R'' and R'''' are independently hydrocarbyl groups having 1 to 8 carbon atoms. Formula RSn(NR'''COR'') ３ A method for forming monoalkyltriamidotin, comprising the step of collecting a solid product represented by [the specified method].

28. The method according to claim 27, wherein the monoalkyl tin triamide has an initial concentration of about 0.1 M to about 8 M, and the solvent is an alkane, an aromatic hydrocarbon, or an ether.

29. The method according to claim 27 or claim 28, wherein the amide is added in stages over a period of at least about two minutes.

30. The method according to any one of claims 27 to 29, wherein the solid product is crystalline and contains about 1 mole percent or less of dialkyltin compound contaminants relative to tin.

31. Monoalkyltriamidotin compound (RSn(NR'''COR'') ３ ) is reacted with an alkali alkoxide compound (QOR', where Q is an alkali metal atom) in an organic solvent to obtain the chemical formula RSn(OR'). ３ A method for forming a monoalkyltin trialalkoxide, comprising the step of forming a product compound represented by the formula (wherein R is a hydrocarbyl group having 1 to 31 carbon atoms, and R', R'' and R''' are independently hydrocarbyl groups having 1 to 10 carbon atoms).

32. The method according to claim 31, wherein the alkoxide donating compound is provided in at least a stoichiometric amount.

33. The method according to claim 31 or claim 32, wherein the solvent is an alkane, an aromatic hydrocarbon, or an ether.

34. A method for purifying monoalkyltin trialkoxide, comprising the step of distilling a blend of monoalkyltin trialkoxide and a tetradentate non-planar complexing agent.

35. The method according to claim 34, wherein the tetradentate non-planar complex-forming agent comprises TREN.

36. The method according to claim 34 or claim 35, wherein the tetradentate non-planar complex-forming agent is present in an amount of about 0.5 mol% to about 15 mol% relative to the molar amount of tin.

37. The alkyl group is R １ R ２ R ３ C-(wherein, R １ and R ２ R is an alkyl group having 1 to 10 carbon atoms independently. ３ The method according to any one of claims 34 to 36, wherein is represented by hydrogen or an alkyl group having 1 to 10 carbon atoms.

38. The method according to any one of claims 34 to 36, wherein the alkyl group comprises isopropyl, tert-butyl, tert-amyl, sec-butyl, or neopentyl.

Images