A germanium-substituted polymethylene borate compound and preparation method thereof

Abstract

The invention belongs to the technical field of organic synthesis and relates to a germanium-substituted polymethylene borate compound and a preparation method thereof. The invention uses a polychlorogermanium compound as a starting raw material, has a safe and simple synthesis method, uses inexpensive and readily available reagents, has mild reaction conditions, and has a wide substrate applicability. Various germanium-substituted polymethylene borate esters can be synthesized using a variety of different germanium metal compounds, such as germanium tetrachloride, phenylgermanium trichloride, methylgermanium trichloride, and benzylgermanium trichloride and bis[(pinacol)boryl]methane in the presence of potassium tert-butoxide and an inert gas atmosphere. Developing an efficient method for preparing germanium-substituted polymethylene borate esters from germanium metal compounds has important practical significance in organic synthesis and industrial application.

Description

Technical Field

[0001] The invention belongs to the technical field of organic synthesis and relates to a germanium-substituted polymethylene borate compound and a preparation method thereof. Background Art

[0002] Germanium, like silicon, tin, and lead, belongs to the carbon group. It is extremely dispersed in nature, with almost no concentrated germanium ores. Therefore, it is called a "scattered metal." Due to its unique physical and chemical properties, organic germanium compounds are widely used in many industrial fields such as anticancer drug synthesis, textile industry, polymerization catalyst synthesis, optical fiber system industry, electronic components industry, etc., playing a huge economic role. For example, in

[0003] "Testing the Negative Ion, Far Infrared, and Antibacterial Properties of Germanium-Containing Fabrics" demonstrates the application of organic germanium to fabrics, achieving excellent antibacterial effects. "Investigation of the Effect of Organic Germanium Functional Finishing on the Wearability of Knitted Underwear Fabrics" discusses its application to textile fabrics to increase their resistance to shrinkage and tensile deformation. Furthermore, "A Resveratrol Sesquioxygermanium Compound, Its Preparation Method, and Application" (CN 102558222A) demonstrates excellent performance in scavenging free radicals, providing antioxidant benefits, inhibiting bacteria, and inhibiting cancer cells.

[0004] It can be seen that organic germanium has a wide range of applications, and the study of its preparation plays an important role in methodology. The synthesis and transformation of organic germanium have a very broad application prospect and research value in organic methodology.

[0005] Among existing methods, organogermanium has been extensively studied in catalytic coupling reactions; however, its synthesis methods are relatively limited and the cost is relatively high. Germanium metal compounds are relatively inexpensive and readily available, and simple conversions from polychlorogermanium compounds to germanium-substituted polymethylene borate esters hold great promise for future applications. Developing an efficient method for preparing organogermanium from germanium metal compounds is of great practical significance in organic synthesis and industrial applications. Summary of the Invention

[0006] In order to overcome the shortcomings of existing methods for preparing germanium-substituted polymethylene borate, the present invention aims to provide a germanium-substituted polymethylene borate compound and a preparation method thereof. The method uses readily available bis[(pinacol)boryl]methane, potassium tert-butoxide, and a germanium metal compound as raw materials to prepare the polymethylene borate compound by a pot process. The method is simple to operate, has mild reaction conditions, and has high yields for multiple substrates with different structures.

[0007] The first aspect of the present invention provides a germanium-substituted polymethylene borate compound, which is represented by formula (I):

[0008]

[0009] The R is selected from substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted alkylaryl, substituted or unsubstituted cycloalkenyl, and substituted or unsubstituted arylalkyl.

[0010] In some specific embodiments of the first aspect of the present invention, R is selected from a linear alkane group having 1 to 6 carbon atoms.

[0011] In some specific embodiments of the first aspect of the present invention, R is selected from a linear olefin group having 2 to 6 carbon atoms.

[0012] In some specific embodiments of the first aspect of the present invention, R is selected from a linear alkyne group having 2 to 6 carbon atoms.

[0013] In some specific embodiments of the first aspect of the present invention, R is selected from a branched alkane group having 3-6 carbon atoms.

[0014] In some specific embodiments of the first aspect of the present invention, R is selected from a branched alkene group having 3 to 6 carbon atoms.

[0015] In some specific embodiments of the first aspect of the present invention, R is selected from a branched alkyne group having 3 to 6 carbon atoms.

[0016] In some specific embodiments of the first aspect of the present invention, R is selected from an alkylaryl group having 7 to 18 carbon atoms.

[0017] In some specific embodiments of the first aspect of the present invention, R is selected from an aryl group having 6 to 18 carbon atoms.

[0018] In some specific embodiments of the first aspect of the present invention, R is selected from a 3-7 membered heterocyclic group.

[0019] In some specific embodiments of the first aspect of the present invention, the hydrogen of R can be optionally replaced by R a Substituted, the R a and independently selected at each occurrence from substituted or unsubstituted monocyclic aryl, substituted or unsubstituted fused ring aryl, substituted or unsubstituted borate, substituted or unsubstituted methyl, substituted or unsubstituted ethyl, substituted or unsubstituted n-propyl, substituted or unsubstituted isopropyl.

[0020] In some specific embodiments of the first aspect of the present invention, the compound of formula (I) is specifically 1b to 4b:

[0021]

[0022] The second aspect of the present invention provides a method for synthesizing the germanium-substituted polymethylene borate compound of the first aspect, comprising: compound a,

[0023] Under an inert gas atmosphere, the germanium metal compound represented by formula (II) reacts with compound a in an alkali and organic solution reaction atmosphere to obtain a germanium-substituted polymethylene borate compound represented by formula (I).

[0024]

[0025] The R is selected from substituted or unsubstituted alkyl, substituted or unsubstituted alkene, substituted or unsubstituted alkynyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted alkylaryl, substituted or unsubstituted cycloalkenyl, substituted or unsubstituted arylalkyl, and halogen, and the X1 is the same as the R;

[0026] In some specific embodiments of the second aspect of the present invention, X1 is different from R, and X1 and X2, X3, and X4 are each independently selected from halogen.

[0027] In some specific embodiments of the second aspect of the present invention, the H on R is arbitrarily replaced by R a Substituted, the R a Each occurrence is independently selected from substituted or unsubstituted monocyclic aryl, substituted or unsubstituted borate, substituted or unsubstituted methyl, substituted or unsubstituted ethyl, substituted or unsubstituted n-propyl, substituted or unsubstituted isopropyl, substituted or unsubstituted benzyl.

[0028] In some specific embodiments of the second aspect of the present invention, the X1 is selected from Ph, Bn, methyl, and the R is the same as X1;

[0029] In some specific embodiments of the second aspect of the present invention, X1 is selected from halogen, and R is

[0030] In some specific embodiments of the second aspect of the present invention, the base is selected from potassium tert-butoxide and sodium tert-butoxide.

[0031] In some specific embodiments of the second aspect of the present invention, the inert gas atmosphere is an argon atmosphere or a nitrogen atmosphere.

[0032] In some specific embodiments of the second aspect of the present invention, the heating temperature is 30-50°C, in some specific preferred embodiments of the second aspect of the present invention, the heating temperature is 35-45°C, and in some specific especially preferred embodiments of the second aspect of the present invention, the heating temperature is 40°C.

[0033] In some specific embodiments of the second aspect of the present invention, the molar ratio of the germanium metal compound, the base, and the compound a is 1:(3-4):(3-4).

[0034] Parameter Description:

[0035] "Room temperature" refers to a temperature from about 10°C to about 40°C. In some embodiments, "room temperature" refers to a temperature from about 20°C to about 30°C; in other embodiments, "room temperature" refers to 20°C, 22.5°C, 25°C, 27.5°C, etc.

[0036] "Alkylaryl" refers to a group in which any hydrogen on the ring is replaced by R c Substituted aryl, wherein R c It is only explained here as saturated or unsaturated alkyl, saturated or unsaturated olefin, saturated or unsaturated alkyne, R c The carbon number of an alkane can contain 1 to 10 carbon atoms, R c The carbon number of an alkene or an alkyne may contain 3 to 6 carbon atoms, more preferably 4 carbon atoms, and exemplary thereof include m R c When they appear, they independently replace the hydrogen on the benzene ring, and m is the hydrogen on the benzene ring replaced by R c The number of substitutions, m, is selected from 1 to 5, further 2, and further examples are R c is a tert-butyl group, m is 2, and the number of tert-butyl groups is 2;

[0037] "Arylalkyl" refers to a group in which any hydrogen is replaced by R d Substituted alkyl, wherein R d Selected from monocyclic aromatic groups or condensed aromatic groups, exemplified by Wherein n is selected from a positive integer of 1 to 5, further 1, and a further example is The Bpin group is a pinacol boron group, with a structure such as:

[0038] "Alkyl" refers to a straight-chain or branched saturated alkyl group.

[0039] "Alkynyl" refers to a straight or branched chain alkyl group containing one, two, three or more carbon-carbon triple bonds.

[0040] "Alkenyl" refers to a straight or branched chain alkyl group containing one, two, three or more carbon-carbon double bonds.

[0041] "Cycloalkyl" refers to a monovalent saturated hydrocarbon, all-carbon cyclic group, non-limiting examples of which include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and the like.

[0042] "Cycloalkenyl" refers to a monovalent cyclic group having at least one carbon-carbon double bond and not aromatic. Non-limiting examples include cyclopentenyl, cyclohexenyl, cycloheptenyl, and the like.

[0043] "Heterocyclyl" refers to a non-aromatic fully saturated ring comprising one or more heteroatoms selected from N, O and S, with the remaining ring atoms being carbon.

[0044] Those skilled in the art will appreciate that the above groups can be named using generally accepted naming systems and symbols, such as Chemical Abstracts Service (CAS) or International Union of Pure and Applied Chemistry (IUPAC) rules.

[0045] Compound a can be made from It can also be represented by express;

[0046] Compound 1b can be made from It can also be done by express;

[0047] Compound 2b can be made from It can also be done by express;

[0048] Compound 3b can be made from It can also be done by express;

[0049] Compound 4b can be prepared by It can also be done by express;

[0050] Beneficial effects:

[0051] The invention uses polychlorogermanium compounds as starting raw materials, and the synthesis method is safe and simple to operate. Reagents used in the reaction are cheap and easily available, the reaction conditions are mild, and the substrate applicability is wide. Specifically, cheap bis[(pinacol)boryl]methane can be used to react with germanium tetrachloride, phenylgermanium trichloride, benzylgermanium trichloride, and methylgermanium trichloride at a mild temperature of 40° C., with a high yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 This is the H NMR spectrum of the sample prepared in Example 1 of the present invention;

[0053] Figure 2 This is the NMR carbon spectrum of the sample prepared in Example 1 of the present invention;

[0054] Figure 3 This is the NMR boron spectrum of the sample prepared in Example 1 of the present invention;

[0055] Figure 4This is the H NMR spectrum of the sample prepared in Example 2 of the present invention;

[0056] Figure 5 This is the NMR carbon spectrum of the sample prepared in Example 2 of the present invention;

[0057] Figure 6 This is the NMR boron spectrum of the sample prepared in Example 2 of the present invention;

[0058] Figure 7 This is the H NMR spectrum of the sample prepared in Example 3 of the present invention;

[0059] Figure 8 This is the NMR carbon spectrum of the sample prepared in Example 3 of the present invention;

[0060] Figure 9 This is the NMR boron spectrum of the sample prepared in Example 3 of the present invention;

[0061] Figure 10 This is the H NMR spectrum of the sample prepared in Example 4 of the present invention;

[0062] Figure 11 This is the NMR carbon spectrum of the sample prepared in Example 4 of the present invention;

[0063] Figure 12 This is the NMR boron spectrum of the sample prepared in Example 4 of the present invention; DETAILED DESCRIPTION

[0064] The present invention is further described below in conjunction with specific examples. It is worth noting that these examples are only used to illustrate the present invention and are not intended to limit the present invention in any way. In practical applications, improvements and adjustments made by technicians based on the present invention still fall within the scope of protection of the present invention. The reaction equations are all shown in the following general formula:

[0065]

[0066] Example 1

[0067]

[0068] In a glove box, potassium tert-butoxide (2.0 mmol, 4.0 equivalents) was added to a tetrahydrofuran solution (5 mL) of bis[(pinacolato)boryl]methane and compound a (CAS: 78782-17-9, 2.0 mmol, 4.0 equivalents) at room temperature and reacted for 6 hours. Germanium tetrachloride (CAS: 10038-98-9, 1.0 equivalents) was then added to the mixed solution. The mixture was removed from the glove box and heated to 40° C. for 16 hours. The reaction was cooled to room temperature and quenched with purified water. Ethyl acetate was added for extraction, dried over anhydrous sodium sulfate, and the solvent was removed under reduced pressure. The crude product was purified by column chromatography using a mixed solvent of petroleum ether and ethyl acetate in a volume ratio of 15:1 as the eluent to obtain germanium-substituted tetramethylene borate in a yield of 65%.

[0069] The hydrogen spectrum, carbon spectrum, boron spectrum, high-resolution mass spectrum, and infrared spectrum data are as follows:

[0070] 1 HNMR (400MHz, CDCl3) δ1.21 (s, 48H), 0.34 (s, 8H). 13 C NMR (101MHz, CDCl3) δ82.5, 25.0. 11 BNMR (128MHz, CDCl3) δ33.45.

[0071] HRMS (ESI-TOF, m / z), chemical formula C 28 H 57 B4GeO8(M+H) + , theoretical mass 639.3639, detected mass 639.3644.

[0072] Example 2

[0073]

[0074] In a glove box, potassium tert-butoxide (1.5 mmol, 3.0 equivalents) was added to a tetrahydrofuran solution (5 mL) of bis[(pinacolato)boryl]methane compound a (CAS: 78782-17-9, 1.5 mmol, 3.0 equivalents) at room temperature and reacted for 6 hours. Phenylgermanium trichloride (CAS: 1074-29-9, 0.5 mmol, 1.0 equivalents) was then added to the mixed solution. The mixture was removed from the glove box and heated to 40° C. for 16 hours. The reaction was cooled to room temperature and quenched with purified water. Ethyl acetate was added for extraction, dried over anhydrous sodium sulfate, and the solvent was removed under reduced pressure. The crude product was purified by column chromatography using a mixed solvent of petroleum ether and ethyl acetate in a volume ratio of 10:1 as the eluent to obtain germanium-substituted phenyl trimethylene borate in a yield of 70%.

[0075] The hydrogen spectrum, carbon spectrum, boron spectrum, high-resolution mass spectrum, and infrared spectrum data are as follows:

[0076] 1 HNMR (400MHz, CDCl3) δ7.63 (dd, J=7.4, 1.9Hz, 2H), 7.30–7.26 (m, 3H), 1.14 (s, 36H), 0.57 (s, 6H). 13 CNMR (101MHz, CDCl3) δ141.6, 133.9, 128.2, 127.4, 82.7, 24.9. 11 BNMR (128MHz, CDCl3) δ33.38, 32.02.

[0077] HRMS (ESI-TOF, m / z) Chemical formula C 27 H 47 B3GeNaO6(M+Na + ), theoretical mass 597.2756, detected mass 597.2762.

[0078] Example 3

[0079]

[0080] In a glove box, potassium tert-butoxide (1.5 mmol, 3.0 equivalents) was added to a tetrahydrofuran solution (5 mL) of bis[(pinacolato)boryl]methane and compound a (CAS: 78782-17-9, 1.5 mmol, 3.0 equivalents) at room temperature and reacted for 6 hours. Benzylgermanium trichloride (CAS: 6181-21-1, 0.5 mmol, 1.0 equivalents) was then added to the mixed solution. The mixture was removed from the glove box and heated to 40° C. for 16 hours. The reaction was cooled to room temperature and quenched with purified water. Ethyl acetate was added for extraction, dried over anhydrous sodium sulfate, and the solvent was removed under reduced pressure. The crude product was purified by column chromatography using a mixed solvent of petroleum ether and ethyl acetate in a volume ratio of 10:1 as the eluent to obtain germanium-substituted benzyl trimethylene borate in a yield of 70%.

[0081] The hydrogen spectrum, carbon spectrum, boron spectrum, high-resolution mass spectrum, and infrared spectrum data are as follows:

[0082] 1 H NMR (400MHz, CDCl3) δ7.21–6.98 (m, 5H), 2.40 (s, 2H), 1.21 (s, 36H), 0.22 (s, 6H). 13 C NMR (101MHz, CDCl3) δ128.3, 128.1, 123.8, 82.7, 26.8, 25.0. 11 B NMR (128MHz, CDCl3) δ35.69.

[0083] HRMS (ESI-TOF, m / z) Chemical formula C 28 H 50 B3GeO6(M+H) + , theoretical quality 589.3100, detection quality 589.3100.

[0084] Example 4

[0085]

[0086] In a glove box, potassium tert-butoxide (1.5 mmol, 3.0 equivalents) was added to a tetrahydrofuran solution (5 mL) of bis[(pinacolato)boryl]methane compound a (CAS: 78782-17-9, 1.5 mmol, 3.0 equivalents) at room temperature and reacted for 6 hours. Methylgermanium trichloride (CAS: 993-10-2, 0.5 mmol, 1.0 equivalents) was then added to the mixed solution. The mixture was removed from the glove box and heated to 40° C. for 16 hours. The reaction was cooled to room temperature and quenched with purified water. Ethyl acetate was added for extraction, dried over anhydrous sodium sulfate, and the solvent was removed under reduced pressure. The crude product was purified by column chromatography using a mixed solvent of petroleum ether and ethyl acetate in a volume ratio of 10:1 as the eluent to obtain germanium methyl trimethylene borate with a yield of 70%.

[0087] The hydrogen spectrum, carbon spectrum, boron spectrum, and high-resolution mass spectrum data are as follows:

[0088] 1 H NMR (400MHz, CDCl3) δ1.20 (s, 36H), 0.29 (s, 3H), 0.27 (s, 6H). 13 C NMR (101MHz, CDCl3) δ82.8, 25.1. 11 B NMR (128MHz, CDCl3) δ34.63.

[0089] HRMS (ESI-TOF, m / z) Chemical formula C 22 H 46 B3GeO6(M+H) + , theoretical mass 513.2780, detected mass 513.2779.

[0090] Example 5

[0091] The test fabric groups A to H were prepared by a dipping and padding method (organic germanium solvent, concentration calculated as elemental germanium, liquid padding rate 100%) → pre-baking (100°C × 3 min) → baking (135°C × 2 min):

[0092] According to the method described in "Test on Negative Ion, Far Infrared and Antibacterial Properties of Germanium-Containing Fabrics", the antibacterial properties of germanium-containing fabrics were tested in accordance with GB / T20944.3-2008 "Evaluation of Antibacterial Properties of Textiles Part 3: Oscillation Method", and the inhibition rates of Candida albicans, Escherichia coli and Staphylococcus aureus were tested.

[0093]

[0094] The test results show that when the organic germanium content is above 0.43 mg / kg, the antibacterial rate of the fabric against Escherichia coli and Staphylococcus aureus is far greater than the 70% requirement in the standard, at 99% and above; and when the organic germanium content increases from 0.43 mg / kg to 0.53 mg / kg, the antibacterial rate of Candida albicans increases from 85% to 99%, which meets the requirements of the national standard.

[0095] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included in the scope of protection of the present application.

Claims

1. A germanium-substituted polymethylene borate compound, characterized in that: Specifically 1b~4b: ， ， ， 。 2. A method for synthesizing a germanium-substituted polymethylene borate compound, comprising: Compound a, , under an inert gas atmosphere, the germanium metal compound represented by formula (II) reacts with compound a in a base and an organic solvent atmosphere to obtain a germanium-substituted polymethylene borate compound represented by formula (I), ； The X1 is selected from Ph, Bn, and methyl, and the X1 is the same as the R; Alternatively, X1 is different from R, X1 and X2, X3, and X4 are each independently selected from halogen, and R is .

3. The method according to claim 2, characterized in that The X2, X3 and X4 are each independently selected from Cl, Br or I.

4. The method according to any one of claims 2 or 3, characterized in that The organic solvent is selected from any one of dichloromethane, tetrahydrofuran, acetonitrile and alcohol.

5. The method according to any one of claims 2 or 3, characterized in that: The heating temperature is 30-50°C.

6. The method according to claim 5, characterized in that The heating temperature is 35-45°C.

7. The method according to claim 5, characterized in that The heating temperature is 40°C.

8. The method according to any one of claims 2 or 3, characterized in that: The molar ratio of the germanium metal compound, the base and the compound a is 1:(3-4):(3-4).

9. The method according to any one of claims 2 or 3, characterized in that: The inert gas atmosphere is a nitrogen atmosphere or an argon atmosphere.

10. The method according to any one of claims 2 or 3, characterized in that: The base is selected from potassium tert-butoxide and sodium tert-butoxide.

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