A preparation method of O,O-boron difluoride complex

Abstract

The invention discloses a method for preparing an O,O-boron difluoride complex. In the presence of a catalyst, an alkynone compound shown in formula (1) and a boron source are reacted in a solvent to obtain an O,O-boron difluoride complex shown in formula (2). The preparation method of the present invention has a simple and mature raw material synthesis process, mild reaction conditions, does not require the introduction of hazardous reagents, is simple to operate, and has an excellent yield. This method provides a new, efficient, and low-cost approach to preparing an O,O-boron difluoride complex.

Description

Technical Field

[0001] The present invention relates to the technical field of organic synthesis, and more particularly to a method for preparing an O,O-boron difluoride complex. Background Art

[0002] O,O-boron difluoride complexes have the characteristics of strong electron transfer ability, high fluorescence quantum yield, relatively stable in air, large molar absorption coefficient, and large Stokes shift (Synthesis, photophysical and electrochemical properties of novel and highly fluorescent difluoroboron flavanone b-diketonate complexes. New J. Chem. 2020, 44, 14615). It is a promising π-π conjugated organic fluorescent material, mainly used in near-infrared dyes, solar cells, OLED materials, molecular ion probes, bioimaging, piezochromic materials, self-assembly materials, nonlinear optical materials, etc.

[0003]

[0004] O,O-boron difluoride complexes are usually constructed through the following three methods:

[0005]

[0006] In general, existing synthetic methods involve multiple steps and require the use of hazardous reagents such as butyl lithium and sodium hydride. The boronation reagent, boron trifluoride etherate, is flammable, easily decomposes, and hydrolyzes. Therefore, developing more convenient, rapid, and safe methods for preparing O,O-boron difluoride complexes is crucial. Summary of the Invention

[0007] The present invention overcomes the defects of the prior art in that the raw material synthesis is complex, hazardous reagents such as butyl lithium and sodium hydride are required, the reaction steps are numerous, and the yield is low. A method for preparing an O,O-boron difluoride complex is provided. The method has a simple and mature raw material synthesis process, simple process operation, excellent yield, and has prospects for industrial production.

[0008] To achieve the above object, the technical solution adopted by the present invention is:

[0009] A method for preparing an O,O-boron difluoride complex comprises reacting an alkynone compound represented by formula (1) and tetrafluoroboric acid as raw materials in a solvent under the action of a catalyst to obtain an O,O-boron difluoride complex represented by formula (2). The reaction formula is as follows:

[0010]

[0011] Among them, R 1 is a C1-C6 alkyl group; or a substituted or unsubstituted C6-C14 aryl group; or a C4-C10 heteroaryl group; the substitution is by one or more of C1-C6 alkyl, C1-C6 alkoxy, halogen, trifluoromethyl, trifluoromethoxy, cyano, N,N-dimethylamino or N,N-diphenylamino; when the substitution is multiple-site substitution, the substituents in the substitution are the same or different;

[0012] R 2 is a C1-C6 alkyl group; or a substituted or unsubstituted C6-C14 aryl group; or a C4-C10 heteroaryl group; the substitution is by one or more of a C1-C6 alkyl group, a C1-C6 alkoxy group, a halogen group, a trifluoromethyl group, a trifluoromethoxy group, an N,N-dimethylamino group, an N,N-diphenylamino group, or a cyano group; when the substitution is a substitution at multiple sites, the substituents in the substitution are the same or different;

[0013] The boron source is tetrafluoroboric acid, boron trifluoride etherate or silver tetrafluoroborate;

[0014] The catalyst is a gold catalyst and / or silver tetrafluoroborate.

[0015] The preparation method of the present invention has simple raw material sources, a wide substrate range, a mature synthesis process, and simple operation, and can meet the research and development and production needs of the organic, chemical, and material fields.

[0016] Preferably, R 1 It is a C1-C4 alkyl group, a C6-C12 aryl group, or a C4-C8 heteroaryl group.

[0017] Preferably, R 2 It is a C1-C4 alkyl group, a C6-C12 aryl group, or a C4-C8 heteroaryl group.

[0018] More preferably, R 2 It is a C6-C12 aryl group.

[0019] Substituent Definitions and General Terms

[0020] The term "alkyl" used in the present invention refers to a saturated, linear, branched or cyclic monovalent hydrocarbon group containing 1 to 6 carbon atoms.

[0021] As used herein, the term "aryl" refers to monocyclic, bicyclic, and tricyclic carbon ring systems containing 6-14 ring atoms, 6-12 ring atoms, or 6-10 ring atoms, wherein at least one ring system is aromatic, wherein each ring system comprises a ring of 3-7 atoms and has one or more points of attachment to the rest of the molecule. The term "aryl" can be used interchangeably with the term "aromatic ring." Examples of aryl groups include phenyl, indenyl, naphthyl, phenanthrene, and anthracene, among others.

[0022] The term "heteroaryl" refers to monocyclic, bicyclic, and tricyclic ring systems containing 5-10 ring atoms, or 5-6 ring atoms, wherein at least one ring system is aromatic and at least one ring system contains one or more heteroatoms, wherein each ring system contains 5-7 ring atoms and has one or more points of attachment to the rest of the molecule. The term "heteroaryl" can be used interchangeably with the terms "heteroaromatic ring" or "heteroaromatic compound." Examples of heteroaryl groups include, but are not limited to, 2-furyl, 3-furyl, 2-thienyl, 3-thienyl, N-imidazolyl, 2-imidazolyl, 4-imidazolyl, 5-imidazolyl, 3-isoxazolyl, 4-isoxazolyl, 5-isoxazolyl, 2-oxazolyl, 4-oxazolyl, 5-oxazolyl, N-pyrrolyl, 2-pyrrolyl, 3-pyrrolyl, 2-pyridyl, 3-pyridyl, 4-pyridyl, 2-pyrimidinyl, 4-pyrimidinyl, 5-pyrimidinyl, and the like.

[0023] The term "alkoxy" means an alkyl group attached to the rest of the molecule via an oxygen atom, wherein the alkyl group has the meaning as defined herein.

[0024] The term "halogen" as used herein refers to fluorine, chlorine, bromine, and iodine.

[0025] Preferably, the molar ratio of the alkynone compound represented by formula (1), the boron source and the catalyst is 1:1-5:0.001-1.5.

[0026] More preferably, the molar ratio of the alkynone compound represented by formula (1), the boron source and the catalyst is 1:1-5:0.01-0.05.

[0027] Preferably, the gold catalyst is one or more of IPrAuCl, SIPrAuCl, IMesAuCl, SIMesAuCl, PPh3AuCl, KAuCl4 or NaAuCl4.

[0028] Preferably, the catalyst is a gold catalyst and silver tetrafluoroborate, and the molar ratio of the gold catalyst to silver tetrafluoroborate is 1:1-150.

[0029] Preferably, the solvent is one or more of acetonitrile, toluene, tetrahydrofuran, 1,4-dioxane, fluorobenzene, ethylene glycol, isopropanol, nitrobenzene, trifluorotoluene or water.

[0030] More preferably, the solvent is a combination of toluene and water, fluorobenzene and water, nitrobenzene and water, or trifluorotoluene and water.

[0031] Preferably, the reaction temperature is 60-150°C.

[0032] More preferably, the reaction temperature is 80-90°C.

[0033] Preferably, the reaction time is 24 to 48 hours.

[0034] More preferably, the reaction time is 30 to 40 hours.

[0035] The alkynone compound represented by formula (1) of the present invention can be purchased directly or prepared by referring to known literature methods.

[0036] As one embodiment, it can be prepared according to the following two operations:

[0037] (1) An alkynyl compound reacts with butyl lithium and then an aldehyde compound is added to generate an alkynol compound, which is then oxidized to an alkynone compound using manganese dioxide (Helvetica Chimica Acta, 2002, vol. 85, #10, p. 3052–3077).

[0038]

[0039] (2) Acid chloride compounds and alkynyl compounds undergo coupling reaction to generate alkynone compounds (Organic and Biomolecular Chemistry, 2019, vol. 17, #17, p. 4225-4229).

[0040]

[0041] Furthermore, as O,O-boron difluoride complexes that can be prepared by the present invention, some are listed below:

[0042]

[0043]

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] The preparation method of the present invention has simple and mature raw material synthesis process, mild reaction conditions, no need to introduce hazardous reagents, simple process operation, and excellent yield, providing a new, efficient and low-cost way to prepare O,O-boron difluoride complex. DETAILED DESCRIPTION

[0046] The present invention is further described below with reference to specific examples, but the examples do not limit the present invention in any form. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the art and can be directly purchased or synthesized by known literature methods.

[0047] Example 1

[0048] This embodiment provides a method for preparing a 1,3-diphenyl-1,3-propanedione boron difluoride complex (2aa), and the specific steps are as follows:

[0049]

[0050] To a reaction flask, 1,3-diphenylprop-2-yn-1-one (1aa, 44.8 mg, 0.2 mmol, 1.0 eq.), silver tetrafluoroborate (0.176 mg, 1.0 mol%), and SIPrAuCl (0.87 mg, 1.0 mol%) were added. Fluorobenzene (5 mL) was added and stirred to dissolve, followed by the addition of aqueous tetrafluoroboric acid (48% wt, 4.0 eq.). The reaction was stirred at 80°C for 40 hours. After completion of the reaction, the mixture was filtered, concentrated, and separated by column chromatography using petroleum ether and ethyl acetate (PE / EA = 3:1) as the eluent to afford the 1,3-diphenyl-1,3-dione boron difluoride complex (2aa, 45 mg, 85%) as a yellow solid.

[0051] 1 H NMR (500MHz, CDCl3) δ8.14 (d, J = 7.7Hz, 4H), 7.69 (t, J = 7.4Hz, 2H), 7.55 (t, J = 7.7Hz, 4H), 7.20 (s, 1H). 13 C NMR (126MHz, CDCl3).δ183.31,135.30,131.97,129.21,128.95,93.45. 19 F NMR (471MHz, CDCl3) δ-139.61,-139.68.

[0052] Examples 2 to 17

[0053] This example provides a series of preparation methods for O,O-boron difluoride complexes. The preparation methods and raw materials are the same as those in Example 1. Different catalysts, boron sources, and solvents are used to prepare 1,3-diphenyl-1,3-propanedione boron difluoride complexes (2aa). The specific results are shown in Table 1:

[0054] Table 1 Examples 2 to 17

[0055]

[0056] Examples 17 to 21

[0057] This example provides a series of preparation methods for O,O-boron difluoride complexes. The preparation methods and raw materials are the same as those in Example 1. Different catalysts and boron sources are used to prepare 1,3-diphenyl-1,3-propanedione boron difluoride complexes (2aa). The specific results are shown in Table 2:

[0058] Table 2 Examples 17 to 21

[0059]

[0060]

[0061] Example 22

[0062] This embodiment provides a method for preparing 1-phenyl-3-(p-tolyl)propane-1,3-dione boron difluoride complex (2ab)

[0063]

[0064] 3-phenyl-1-(p-tolyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-phenyl-3-(p-tolyl)propane-1,3-dione boron difluoride complex (2ab, 57 mg, 99%).

[0065] 1 H NMR (500MHz, CDCl3) δ8.13(d,J=7.6Hz,2H),8.05(d,J=8.0Hz,2H),7.68(t,J=7. 4Hz,1H),7.55(t,J=7.7Hz,2H),7.35(d,J=8.0Hz,2H),7.16(s,1H),2.47(s,3H). 13 CNMR(126MHz, CDCl3).δ183.21,182.58,147.07,135.03,132.14,130.00,129.15,129.13,128.81,93.07,21.99. 19F NMR (471MHz, CDCl3) δ-139.90,-139.96.

[0066] Example 23

[0067] This embodiment provides a method for preparing 1-phenyl-3-(p-fluorophenyl)propane-1,3-dione boron difluoride complex (2ac)

[0068]

[0069] 3-phenyl-1-(p-fluorophenyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-phenyl-3-(p-fluorophenyl)propane-1,3-dione boron difluoride complex (2ac, 49 mg, 84%).

[0070] 1 H NMR (400MHz, DMSO-d6) δ8.48(dd,J=9.2,6.0Hz,2H),8.37(d,J=8.7Hz,2H),7.92–7.75(m,2H),7.66(t,J=8.3Hz,2H),7.50(d,J=18.5Hz,2H). 13 C NMR (101MHz, DMSO). δ182.50 (d, J = 129.6Hz), 167.16 (d, J = 256.7Hz), 136.35, 133.16, 131.72, 129.85, 128.34, 117.18 (d, J = 22.4Hz), 94.85. 19 F NMR (471MHz, CDCl3) δ-100.37,-139.51,-139.57.

[0071] Example 24

[0072] This embodiment provides a method for preparing 1-phenyl-3-(p-bromophenyl)propane-1,3-dione boron difluoride complex (2ad)

[0073]

[0074] 3-phenyl-1-(p-bromophenyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-phenyl-3-(p-bromophenyl)propane-1,3-dione boron difluoride complex (2ad, 62 mg, 89%).

[0075] 1H NMR (500MHz, CDCl3) δ8.15(d,J=7.7Hz,2H),8.00(d,J=8.4Hz,2H),7.75–7.68(m,3H),7.57(t,J=7.7Hz,2H),7.16(s,1H). 13 C NMR (126MHz, CDCl3). δ182.00,135.57,132.64,131.83,130.84,130.15,129.28,129.06,93.35. 19 F NMR(471MHz, CDCl3)δ-139.27,-139.33.

[0076] Example 25

[0077] This embodiment provides a method for preparing 1-phenyl-3-(p-chlorophenyl)propane-1,3-dione boron difluoride complex (2ae)

[0078]

[0079] 3-phenyl-1-(p-chlorophenyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-phenyl-3-(p-chlorophenyl)propane-1,3-dione boron difluoride complex (2ae, 46 mg, 75%).

[0080] 1 H NMR (500MHz, CDCl3) δ8.13–8.07(m,3H),7.88(dd,J=4.9,1.2Hz,1H),7.67(t,J=7.4Hz,1H),7.54(t,J=7.8Hz,2H),7.28(d,J=4.2Hz,1H),6.99(s,1H). 13 C NMR (126MHz, CDCl3).δ149.59,135.19,129.16,128.90,121.75,114.33. 19 F NMR(471MHz, CDCl3)δ-139.27,-139.33.

[0081] Example 26

[0082] This embodiment provides a method for preparing 1-phenyl-3-(p-methoxyphenyl)propane-1,3-dione boron difluoride complex (2af)

[0083]

[0084] 3-phenyl-1-(p-methoxyphenyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-phenyl-3-(p-methoxyphenyl)propane-1,3-dione boron difluoride complex (2af, 56 mg, 91%).

[0085] 1 H NMR (500MHz, CDCl3) δ8.05(dd,J=14.5,8.3Hz,4H),7.59(t,J=7.4Hz,1H),7.46(t,J=7.8Hz,2H),7.02(s,1H),6.95(d,J=8.9Hz,2H),3.85(s,3H). 13 C NMR (126MHz, CDCl3).δ181.3,180.5,164.8,133.7,131.3,130.6,128.1,127.6,123.1,113.7,91.5,54.8. 19 F NMR (471MHz, CDCl3) δ-140.28,-140.35.

[0086] Example 27

[0087] This embodiment provides a method for preparing 1-(3-fluorophenyl)-3-phenylpropane-1,3-dione boron difluoride complex (2ag)

[0088]

[0089] 1-(3-Fluorophenyl)-3-phenylprop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(3-fluorophenyl)-3-phenylpropane-1,3-dione boron difluoride complex (2ag, 42 mg, 81%).

[0090] 1 H NMR (500MHz, CDCl3) δ8.15(d,J=7.0Hz,2H),7.93(d,J=7.9Hz,1H),7.81(dt,J=9.5,2.3Hz ,1H),7.72(t,J=7.4Hz,1H),7.61–7.51(m,3H),7.39(td,J=7.8,1.7Hz,1H),7.17(s,1H). 13C NMR(126MHz, CDCl3).δ184.24,181.70,163.90,161.92,135.72,134.21,134.16,131.71, 130.95,130.89,129.31,129.15,124.60,124.57,122.25,122.08,115.69,115.50,93.73. 19 F NMR(471MHz, CDCl3)δ-110.42,-139.14,-139.20.IR(KBr,cm -1 ):3555,3212,3168,3124,2360,1639,1401,1085,989,534.

[0091] Example 28

[0092] This embodiment provides a method for preparing 1-(2-methylphenyl)-3-phenylpropane-1,3-dione boron difluoride complex (2ah)

[0093]

[0094] 1-(2-methylphenyl)-3-phenylprop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(2-methylphenyl)-3-phenylpropane-1,3-dione difluoride boron complex (2ak, 57 mg, 99%).

[0095] 1 H NMR (500MHz, CDCl3) δ8.11(d,J=7.8Hz,2H),7.73(d,J=7.8Hz,1H),7.68(t,J=7.6Hz,1H),7.54(t ,J=7.8Hz,2H),7.49(t,J=7.6Hz,1H),7.33(t,J=6.2Hz,2H),6.94(d,J=3.4Hz,1H),2.63(s,3H). 13 C NMR (126MHz, CDCl3).δ87.8,183.0,139.7,135.4,133.5,132.7,132.4,131.8,130.0,129.2,129.0,126.3,97.2,21.4. 19 F NMR (471 MHz, CDCl3) δ-139.24.

[0096] Example 29

[0097] This embodiment provides a method for preparing 1-(4-cyanophenyl)-3-phenylpropane-1,3-dione boron difluoride complex (2ai)

[0098]

[0099] 1-(4-cyanophenyl)-3-phenylprop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-cyanophenyl)-3-phenylpropane-1,3-dione boron difluoride complex (2ai, 26 mg, 43%).

[0100] 1 H NMR (500MHz, CDCl3) δ8.09(d,J=8.4Hz,2H),8.02(d,J=7.4Hz,2H),7.81(d,J=8.4Hz,2H),7.63(d,J=7.4Hz,1H),7.54(t,J=7.5Hz,2H),6.89(s,1H). 13 C NMR(126MHz,DMSO).δ187.6,182.5,138.8,134.8,134.8,134.1,134.0,133.4,13 3.2,129.5,129.4,128.5,128.4,128.0,128.0,127.9,118.7,115.1,94.8,94.8. 19 F NMR(471MHz,CDCl3)δ-138.72,-138.78.IR(KBr,cm -1 ):3505,3165,3111,2360,1639,1400,1290,1088,989,536.

[0101] Example 30

[0102] This embodiment provides a method for preparing 1-(4-trifluoromethylphenyl)-3-phenylpropane-1,3-dione boron difluoride complex (2aj)

[0103]

[0104] 1-(4-trifluoromethylphenyl)-3-phenylprop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-trifluoromethylphenyl)-3-phenylpropane-1,3-dione boron difluoride complex (2aj, 60 mg, 88%).

[0105] 1H NMR (500MHz, CDCl3) δ8.31(d,J=8.5Hz,2H),7.83(d,J=8.5Hz,2H),7.71–7.62(m,2H),7.57–7.48(m,1H),7.45(t,J=7.4Hz,2H). 13 C NMR (126MHz, CDCl3) δ176.2,139.7,133.3,132.5,131.4,129.8,128.9,119.5,117.9,117.2,95.2,86.4. 19 F NMR(471MHz,CDCl3)δ-139.24.IR(KBr,cm -1 ):3509,3184,2359,1638,1401,1087,990,670,558.

[0106] Example 31

[0107] This embodiment provides a method for preparing 1-(4-tert-butylphenyl)-3-phenylpropane-1,3-dione boron difluoride complex (2ak)

[0108]

[0109] 1-(4-tert-butylphenyl)-3-phenylprop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-tert-butylphenyl)-3-phenylpropane-1,3-dione difluoride boron complex (2ak, 51 mg, 78%).

[0110] 1 H NMR (500MHz, CDCl3) δ8.12(dd,J=7.9,1.5Hz,2H),8.08(d,J=8.3Hz,2H),7.67(t,J=7.4Hz,1H),7.59–7.48(m,4H),7.18(s,1H),1.36(s,9H). 13 C NMR (126MHz, CDCl3) δ183.2,182.6,159.9,135.0,132.1,129.2,129.1,128.8,126.3,93.2,35.5,31.0. 19 F NMR(471MHz,CDCl3)δ-139.40.IR(KBr,cm -1 ):3462,3173,2360,1637,1401,1292,1088,990,853,766,535.

[0111] Example 32

[0112] This embodiment provides a method for preparing 1-(3-methylphenyl)-3-phenylpropane-1,3-dione difluoride boron complex (2al)

[0113]

[0114] 1-(3-Methylphenyl)-3-phenylprop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(3-methylphenyl)-3-phenylpropane-1,3-dione difluoride boron complex (2al, 51 mg, 90%).

[0115] 1 H NMR (500MHz, CDCl3) δ8.11(d,J=7.8Hz,2H),7.91(d,J=12.4Hz,2H),7.66(t,J=7.3Hz,1H),7 .52(t,J=7.6Hz,2H),7.47(d,J=7.5Hz,1H),7.41(t,J=7.6Hz,1H),7.18(s,1H),2.43(s,3H). 13 C NMR (126MHz, CDCl3) δ183.41,182.91,139.23,136.30,135.28,131.86,131.76,129.44,129.19,129.08,128.93,126.26,93.49,21.33. 19 F NMR (471MHz, CDCl3) δ-139.03,-139.10,-139.14.

[0116] Example 33

[0117] This embodiment provides a method for preparing 1-(4-ethylphenyl)-3-phenylpropane-1,3-dione boron difluoride complex (2am)

[0118]

[0119] 1-(4-ethylphenyl)-3-phenylprop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-ethylphenyl)-3-phenylpropane-1,3-dione boron difluoride complex (2am, 59 mg, 99%).

[0120] 1H NMR (500MHz, CDCl3) δ8.12(d,J=7.8Hz,2H),8.06(d,J=8.0Hz,2H),7.67(t,J=7.1Hz,1H),7.54(t ,J=7.6Hz,2H),7.36(d,J=7.9Hz,1H),7.17(s,1H),2.75(q,J=7.2Hz,2H),1.28(t,J=7.6Hz,3H). 13 C NMR (126MHz, CDCl3) δ183.2,182.5,153.2,129.3,129.2,128.8,93.1,29.2,15.0. 19 F NMR (471MHz, CDCl3) δ-139.61,-139.67.

[0121] Example 34

[0122] This embodiment provides a method for preparing 1-(naphthalene-2-yl)-3-phenylpropane-1,3-dione boron difluoride complex (2an)

[0123]

[0124] 1-(Naphthalene-2-yl)-3-phenylprop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(Naphthalene-2-yl)-3-phenylpropane-1,3-dione boron difluoride complex (2an, 44 mg, 73%).

[0125] 1 H NMR (500MHz, CDCl3) δ8.53(d,J=8.6Hz,1H),8.13(d,J=7.3Hz,2H),8.07(d,J=8.2Hz,1H),7.99( dd,J=7.3,1.3Hz,1H),7.90(d,J=1.4Hz,2H),7.75–7.62(m,4H),7.61–7.45(m,7H),7.09(s,1H). 13 C NMR (126MHz, CDCl3) δ187.3,183.0,135.5,134.9,133.9,131.8,131.0,130.3,129.9,129.3,129.1,129.0,128.6,127.0,125.2,124.7,98.2. 19 F NMR (471MHz, CDCl3) δ-138.81,-138.88.

[0126] Example 35

[0127] This embodiment provides a method for preparing 1-(4-trifluoromethoxyphenyl)-3-phenylpropane-1,3-dione boron difluoride complex (2ao)

[0128]

[0129] 1-(4-trifluoromethoxyphenyl)-3-phenylprop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-trifluoromethoxyphenyl)-3-phenylpropane-1,3-dione boron difluoride complex (2ao, 41 mg, 57%).

[0130] 1 H NMR (500MHz, CDCl3) δ8.17(dd,J=20.9,8.1Hz,4H),7.72(t,J=7.3Hz,1H),7.57(t,J=7.6Hz,2H),7.37(d,J=8.4Hz,2H),7.20(s,1H). 13 C NMR (126MHz, CDCl3) δ182.64 (d, J=250.6Hz).154.1,154.1,135.6,131.0,129.3,129.1,120.6,120.6,93.4. 19 FNMR(471MHz, CDCl3)δ-63.26,-139.73,-139.79.

[0131] Example 36

[0132] This embodiment provides a method for preparing 1-phenyl-3-(thiophene-2-yl)propane-1,3-dione difluoride boron complex (2ap)

[0133]

[0134] 3-phenyl-1-(thiophen-2-yl)propyl-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-phenyl-3-(thiophen-2-yl)propane-1,3-dione boron difluoride complex (2ap, 44 mg, 76%).

[0135] 1 H NMR (500MHz, CDCl3) δ8.41(s,1H),8.06(d,J=7.8Hz,2H),7.77–7.58(m,2H),7.49(t,J=7.7Hz,2H),7.42(s,1H),6.99(s,1H). 13C NMR (126MHz, CDCl3) δ182.79,177.42,135.86,135.63,135.14,131.84,129.15,128.79,127.83,126.53,94.02. 19 F NMR (471MHz, CDCl3) δ-139.34,-139.40.

[0136] Example 37

[0137] This embodiment provides a method for preparing 1-phenyl-3-(furan-2-yl)propane-1,3-dione boron difluoride complex (2aq)

[0138]

[0139] 3-phenyl-1-(furan-2-yl)propyl-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-phenyl-3-(furan-2-yl)propane-1,3-dione boron difluoride complex (2aq, 32 mg, 61%).

[0140] 1 H NMR(500MHz, CDCl3)δ8.14(d,2H),7.79(d,J=1.7Hz,1H),7.72–7.65(m,1H),7.61 (d,J=3.7Hz,1H),7.55(t,J=7.7Hz,2H),7.10(s,1H),6.74(dd,J=3.7,1.6Hz,1H). 13 C NMR (126MHz, CDCl3).δ149.59,135.19,129.16,128.90,121.75,114.33. 19 F NMR (471MHz, CDCl3) δ-140.21,-140.27.

[0141] Example 38

[0142] This embodiment provides a method for preparing 1-phenylhexane-1,3-dione difluoride boron complex (2ar)

[0143]

[0144] 1-Phenyl-1-hexyn-3-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-phenylhexane-1,3-dione difluoride boron complex (2ar, 25 mg, 21%).

[0145] 1 H NMR(500MHz, CDCl3)δ8.06(d,J=7.8Hz,2H),7.68(t,J=7.4Hz,1H),7.53(t,J=7.7Hz, 2H), 6.59 (s, 1H), 2.60 (t, J = 7.5Hz, 2H), 1.81 (q, J = 7.4Hz, 2H), 1.03 (t, J = 7.4Hz, 3H). 13 C NMR (126MHz, CDCl3).δ196.0,182.9,135.4,131.4,129.2,129.0,96.9,39.9,29.7,19.6,13.6. 19 F NMR(471MHz, CDCl3)δ-139.09.-139.10.-139.15.-139.16.

[0146] Example 39

[0147] This embodiment provides a method for preparing 1-(4-butylphenyl)-3-(4-methoxyphenyl)propane-1,3-dione boron difluoride complex (2as)

[0148]

[0149] 3-(4-butylphenyl)-1-(4-methoxyphenyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-butylphenyl)-3-(4-methoxyphenyl)propane-1,3-dione boron difluoride complex (2as, 55 mg, 77%).

[0150] 1 H NMR(500MHz, CDCl3)δ8.67–7.85(m,2H),7.32(d,J=8.2Hz,2H),7.06(s,1H),7.01–6.62(m,2H), 3.91(s,3H),2.69(t,J=7.6Hz,2H),1.91–1.41(m,2H),1.52–1.26(m,2H),0.94(t,J=7.4Hz,3H). 13 C NMR(126MHz, CDCl3).δ181.61,181.47,165.57,151.23,131.47,129.68,129.19,128.83 ,124.28,114.62,92.14,77.30,77.25,77.05,76.79,55.77,35.89,33.09,22.34,13.88. 19F NMR (471MHz, CDCl3) δ-140.41,-140.44,-140.47,-140.50.

[0151] Example 40

[0152] This embodiment provides a method for preparing 1-(4-bromophenyl)-3-(4-methoxyphenyl)propane-1,3-dione boron difluoride complex (2at)

[0153]

[0154] 3-(4-bromophenyl)-1-(4-methoxyphenyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-bromophenyl)-3-(4-methoxyphenyl)propane-1,3-dione boron difluoride complex (2at, 65 mg, 85%).

[0155] 1 H NMR (500MHz, CDCl3) δ88.16 (s, 1H), 7.70–7.45 (m, 5H), 7.26 (s, 1H), 6.99 (d, J = 8.8Hz, 2H), 3.90 (s, 3H). 13 C NMR (126MHz, CDCl3).δ176.4,164.6,134.2,132.1,132.0,130.2,125.3,119.3,114.0,90.9,87.8,55.6. 19 F NMR (471MHz, CDCl3) δ-139.34,-139.40.

[0156] Example 41

[0157] This embodiment provides a method for preparing 1-(4-bromophenyl)-3-(4-chlorophenyl)propane-1,3-dione boron difluoride complex (2au)

[0158]

[0159] 3-(4-bromophenyl)-1-(4-chlorophenyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-bromophenyl)-3-(4-chlorophenyl)propane-1,3-dione boron difluoride complex (2au, 58mg, 76%).

[0160] 1H NMR (500MHz, CDCl3) δ8.23–8.08(m,2H),7.66–7.56(m,2H),7.54(dd,J=8.5,1.7Hz,2H),7.53–7.46(m,2H),7.26(s,1H). 13 C NMR (126MHz, CDCl3). δ176.5,140.9,135.1,134.4,132.2,130.9,129.1,125.8,118.8,92.2,87.4. 19 F NMR(471MHz, CDCl3)δ-139.29,-139.36.

[0161] Example 42

[0162] This embodiment provides a method for preparing 1-(4-cyanophenyl)-3-(4-ethyl)propane-1,3-dione boron difluoride complex (2av)

[0163]

[0164] 3-(4-cyanophenyl)-1-(4-ethylphenyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-bromophenyl)-3-(4-ethylphenyl)propane-1,3-dione boron difluoride complex (2av, 33 mg, 51%).

[0165] 1 H NMR (500MHz, CDCl3) δ8.20(d,J=8.1Hz,2H),8.09(d,J=8.0Hz,2H),7.82(d,J=8.1Hz, 2H),7.40(d,J=8.0Hz,2H),7.20(s,1H),2.78(q,J=7.5Hz,2H),1.30(t,J=7.4Hz,3H). 13 C NMR (126MHz, CDCl3).δ185.0,179.6,154.4,136.0,132.7,129.8,129.1,128.9,128.9,117.6,117.6,94.1,29.3,14.9. 19 F NMR (471MHz, CDCl3) δ-139.03,-139.10,-139.14.

[0166] Example 43

[0167] This embodiment provides a method for preparing 1-(4-cyanophenyl)-3-(4-methoxyphenyl)propane-1,3-dione boron difluoride complex (2aw)

[0168]

[0169] 3-(4-cyanophenyl)-1-(4-methoxyphenyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-cyanophenyl)-3-(4-methoxyphenyl)propane-1,3-dione boron difluoride complex (2aw, 52 mg, 78%).

[0170] 1 H NMR (500MHz, DMSO) δ8.47(dd,J=15.9,8.4Hz,4H),8.14(d,J=8.2Hz,2H),7.97(s,1H),7.23(s,1H),6.57(s,1H),3.96(s,3). 13 C NMR (126MHz, DMSO).δ183.7,178.4,167.0,136.1,133.5,133.4,129.7,123.6,118.5,116.9,115.7,95.3,56.7. 19 F NMR(471MHz,DMSO)δ-137.14,-137.21.

[0171] Example 44

[0172] This embodiment provides a method for preparing 1-(4-trifluoromethylphenyl)-3-(4-methoxyphenyl)propane-1,3-dione boron difluoride complex (2ax)

[0173]

[0174] 3-(4-trifluoromethylphenyl)-1-(4-methoxyphenyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-trifluoromethylphenyl)-3-(4-methoxyphenyl)propane-1,3-dione boron difluoride complex (2ax, 71 mg, 96%).

[0175] 1 H NMR (500MHz, CDCl3) δ8.18(dd,J=18.0,8.6Hz,1H),7.78(d,J=8.2Hz,1H),7.12(s,0H),7.03(d,J=8.9Hz,0H),3.95(s,1H).13 C NMR (126MHz, CDCl3).δ183.5,179.3,166.4,135.6,135.4,132.1,128.8,126.0,126.0,126.0,124.4,123.7,122.3,114.9,93.2,55.9. 19 F NMR(471MHz,CDCl3)δ-63.26,-139.70,-139.79.IR(KBr,cm -1 ):3456,3147,2360,1636,1401,1088,990,539.

[0176] Example 45

[0177] This embodiment provides a method for preparing 1-(4-fluorophenyl)-3-(4-methoxyphenyl)propane-1,3-dione boron difluoride complex (2ay)

[0178]

[0179] 3-(4-fluorophenyl)-1-(4-methoxyphenyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-fluorophenyl)-3-(4-methoxyphenyl)propane-1,3-dione boron difluoride complex (2ay, 63 mg, 99%).

[0180] 1 H NMR (500MHz, DMSO) δ8.43(d,J=8.7Hz,2H),8.19(dd,J=25.0,8.9Hz,2H),7.87(s,1H),7.68(dt,J=28.3,7.2Hz,2H),7.23(d,J=8.7Hz,2H). 13 C NMR(126MHz, DMSO).δ181.20(d,J=483.7Hz),179.3,166.7,162.81(d,J=245.3Hz),134.5,134 .4,133.1,132.0,131.9,125.4,123.7,122.41(d,J=21.4Hz),116.0,115.8,115.6,94.5,56.6. 19 FNMR(471MHz,DMSO)δ-111.48,-111.65,-137.43,-137.50.IR(KBr,cm -1):3454,3133,2359,1637,1401,1293,1089,990,850,662,538.

[0181] Example 46

[0182] This embodiment provides a method for preparing 1-(4-methylphenyl)-3-(thiophen-2-yl)propane-1,3-dione boron difluoride complex (2az)

[0183]

[0184] 3-(4-methylphenyl)-1-(thiophen-2-yl)propyl-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-methylphenyl)-3-(thiophen-2-yl)propane-1,3-dione boron difluoride complex (2az, 58 mg, 99%).

[0185] 1 H NMR (500MHz, Acetone-d6) δ8.51(d,J=4.0Hz,1H),8.26(d,J=5.0Hz,1H),8.20(d, J=8.2Hz,2H),7.63(s,1H),7.47(d,J=8.1Hz,2H),7.45–7.37(m,1H),2.48(s,3H). 13 C NMR (126MHz, Acetone).δ205.3,181.7,176.8,146.8,138.5,137.2,136.1,130.0,129.9,129.4,129.0,92.8,21.0. 19 F NMR(471MH,Acetone)δ-140.90,-140.96.

[0186] Example 47

[0187] This embodiment provides a method for preparing 1-(3-methylphenyl)-3-(4-fluorophenyl)propane-1,3-dione boron difluoride complex (2ba)

[0188]

[0189] 3-(3-methylphenyl)-1-(4-fluorophenyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(3-methylphenyl)-3-(4-fluorophenyl)propane-1,3-dione boron difluoride complex (2ba, 55 mg, 91%).

[0190] 1 H NMR (500MHz, CDCl3) δ8.21–8.11(m,2H),7.97–7.88(m,2H),7.50(d,J=7.6Hz ,1H),7.43(t,J=7.7Hz,1H),7.23(t,J=8.5Hz,3H),7.13(s,1H),2.45(s,3H). 13 C NMR(126MHz, CDCl3).δ183.60,181.52,167.07(d,J=259.2Hz),139.27,136.31,131.81,13 1.72,131.64,129.26(d,J=45.1Hz),128.27,126.23,116.61(d,J=22.1Hz),93.16,21.32. 19 F NMR(471MHz, CDCl3)δ-100.58,-139.52,-139.58.IR(KBr,cm -1 ):3512,3444,3125,1636,1400,1296,1150,1088,854,777,652,528.

[0191] Example 48

[0192] This embodiment provides a method for preparing 1-(4-methoxyphenyl)-3-(thiophen-2-yl)propane-1,3-dione boron difluoride complex (2bb)

[0193]

[0194] 3-(4-methoxyphenyl)-1-(thiophen-2-yl)propyl-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-methoxyphenyl)-3-(thiophen-2-yl)propane-1,3-dione boron difluoride complex (2bb, 34 mg, 55%).

[0195] 1 H NMR (500MHz, CDCl3) δ7.98 (dd, J=3.8, 1.3Hz, 1H), 7.70 (dd, J=4.9, 1.3Hz, 1H), 7.6 1(d,J=8.8Hz,2H),7.18(dd,J=4.9,3.8Hz,1H),6.92(d,J=8.8Hz,2H),3.85(s,3H). 13C NMR (126MHz, CDCl3).δ169.9,161.8,145.1,135.1,134.9,134.7,128.3,114.5,111.7,93.0,86.4,55.5. 19 F NMR (471MHz, CDCl3) δ-139.34,-139.40.

[0196] Example 49

[0197] This embodiment provides a method for preparing 1-(2-methylphenyl)-3-(4-methoxyphenyl)propane-1,3-dione boron difluoride complex (2bc)

[0198]

[0199] 3-(2-methylphenyl)-1-(4-methoxyphenyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(2-methylphenyl)-3-(4-methoxyphenyl)propane-1,3-dione boron difluoride complex (2bc, 66 mg, 99%).

[0200] 1 H NMR (500MHz, CDCl3) δ8.10(d,J=8.9Hz,2H),7.69(d,J=7.6Hz,1H),7.46(t,J=7.0Hz, 1H),7.33–7.28(m,2H),7.01(d,J=9.0Hz,2H),6.82(s,1H),3.91(s,3H),2.61(s,3H). 13 C NMR (126MHz, CDCl3) δ186.0,182.1,165.9,139.2,133.2,132.9,132.2,131.7,129.6,126.2,124.0,114.7,96.4,55.8,21.2. 19 F NMR (471MHz, CDCl3) δ-139.95,-140.01.

[0201] Example 50

[0202] This embodiment provides a method for preparing 1-(naphthalene-2-yl)-3-(p-tolyl)propane-1,3-dione boron difluoride complex (2bd)

[0203]

[0204] 3-(naphthalene-2-yl)-1-(p-tolyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(naphthalene-2-yl)-3-(p-tolyl)propane-1,3-dione boron difluoride complex (2bd, 46 mg, 69%).

[0205] 1 H NMR (500MHz, CDCl3) δ8.54(d,J=8.5Hz,1H),8.09(d,J=8.2Hz,1H),8.06(d,J=8.0Hz,2H),8.00(d,J=7.2Hz,1H),7.93( d,J=8.1Hz,1H),7.66(t,J=7.6Hz,1H),7.58(dt,J=15.2,7.7Hz,2H),7.36(d,J=8.0Hz,2H),7.07(s,1H),2.48(s,3H). 13 C NMR (126MHz, CDCl3) δ186.5,183.0,147.3,134.5,133.9,131.3,130.3,13 0.1,129.6,129.3,129.1,128.9,128.5,127.0,125.3,124.7,98.0,22.1. 19 F NMR(471MHz,CDCl3)δ-139.21,-139.27.IR(KBr,cm -1 ):3445,3139,2360,1634,1401,1088,990,855,533.

[0206] Example 51

[0207] This embodiment provides a method for preparing 1-(4-trifluoromethoxyphenyl)-3-(4-methylphenyl)propane-1,3-dione boron difluoride complex (2be)

[0208]

[0209] 3-(4-trifluoromethoxyphenyl)-1-(4-methylphenyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-trifluoromethoxyphenyl)-3-(4-methylphenyl)propane-1,3-dione boron difluoride complex (2be, 66 mg, 89%).

[0210] 1H NMR (500MHz, CDCl3) δ8.15(d,J=8.6Hz,2H),8.02(d,J=8.0Hz,2H),7.33(d,J=8.1Hz,4H),7.13(s,1H),2.46(s,3H). 13 C NMR (126MHz, CDCl3) δ 182.18 (d, J = 390.7Hz), 153.9, 147.5, 130.8, 129.42 (dd, J = 18.8Hz), 122.92 (d, J = 415.9Hz), 120.6, 119.2, 93.1, 22.0. 19 F NMR(471MHz, CDCl3)δ-57.54,-139.41,-139.47.IR(KBr,cm -1 ):3404,3109,2360,1628,1400,1293,1087,990,856,764,617,534.

[0211] Example 52

[0212] This embodiment provides a method for preparing 1,3-bis(4-methoxyphenyl)propane-1,3-dione boron difluoride complex (2bf)

[0213]

[0214] 1,3-bis(4-methoxyphenyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1,3-bis(4-methoxyphenyl)propane-1,3-dione boron difluoride complex (2bf, 39 mg, 59%).

[0215] 1 H NMR (500MHz, CDCl3) δ8.12 (d, J = 9.0Hz, 4H), 7.01 (s, 4H), 3.92 (s, 6H). 13 C NMR (126MHz, CDCl3) δ180.8,171.7,165.3,164.1,132.4,131.3,124.5,121.6,114.6,113.8,91.5,55.8,55.5. 19 F NMR (471MHz, CDCl3) δ-140.93,-140.99.

[0216] Example 53

[0217] This example provides a method for preparing 1-(4-methoxyphenyl)-3-(3,5-dimethylphenyl)propane-1,3-dione boron difluoride complex (2bg)

[0218]

[0219] 3-(4-methoxyphenyl)-1-(3,5-dimethylphenyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-methoxyphenyl)-3-(3,5-dimethylphenyl)propane-1,3-dione boron difluoride complex (2bg, 58 mg, 88%).

[0220] 1 H NMR (500MHz, CDCl3) δ8.14(d,J=8.8Hz,2H),7.72(s,2H),7.29(s,1H),7.07(s,1H),7.02(d,J=8.8Hz,2H),3.93(s,3H),2.41(s,6H). 13 C NMR (126MHz, CDCl3) δ182.0,165.6,138.9,136.6,132.2,131.6,126.5,124.3,114.6,92.5,55.8,21.2. 19 F NMR(471MHz,DMSO)δ-137.65,-137.71.IR(KBr,cm -1 ):3451,3158,2360,1637,1401,1292,1088,990,667,537.

[0221] Example 54

[0222] This embodiment provides a method for preparing 1-(4-methoxyphenyl)-3-(furan-2-yl)propane-1,3-dione boron difluoride complex (2bh)

[0223]

[0224] 3-(4-methoxyphenyl)-1-(furan-2-yl)propyl-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-methoxyphenyl)-3-(furan-2-yl)propane-1,3-dione boron difluoride complex (2bh, 39 mg, 66%).

[0225] 1H NMR(500MHz,DMSO-d6)δ8.34(s,1H),8.29(d,J=8.7Hz,2H),8.07(d,J=3.8Hz ,1H),7.52(s,1H),7.20(d,J=8.8Hz,2H),6.98(d,J=3.1Hz,1H),3.93(s,3H). 13 CNMR(126MHz,DMSO)δ180.8,170.0,166.0,152.1,147.6,132.3,129.6,123.8,123.7,115.5,115.2,114.8,92.6,56.5. 19 F NMR(471MHz,DMSO)δ-138.19,-138.25.

[0226] Example 55

[0227] This embodiment provides a method for preparing 1-(4-fluorophenyl)-3-(furan-2-yl)propane-1,3-dione boron difluoride complex (2bi)

[0228]

[0229] 3-(4-Fluorophenyl)-1-(furan-2-yl)propyl-2-yn-1-one was used to replace the 1,3-diphenylprop-2-yn-1-one in Example 1. The other materials and operations remained unchanged to obtain 1-(4-fluorophenyl)-3-(furan-2-yl)propane-1,3-dione boron difluoride complex (2bi, 44 mg, 79%).

[0230] 1 H NMR (500MHz, CDCl3) δ8.17(dd,J=8.7,5.1Hz,2H),7.80(s,1H),7.62(d,J=3.7Hz,1H),7.23(t,J=8.5Hz,2H),7.04(s,1H),6.81–6.69(m,1H). 13 C NMR (126MHz, CDCl3) δ181.3, 171.6, 167.08 (d, J = 259.3Hz), 149.7, 148.3, 131.7, 131.6, 128.3, 121.9, 116.61 (d, J = 22.2Hz), 114.4, 92.2. 19 F NMR(471MHz,CDCl3)δ-100.62,-140.34,-140.41.IR(KBr,cm -1):3441,3168,2359,1634,1501,1400,1157,1089,759,540.

[0231] Example 56

[0232] This embodiment provides a method for preparing 1-(4-(diphenylamino)phenyl)-3-(m-tolyl)propane-1,3-dione boron difluoride complex (2bj)

[0233]

[0234] 1-(4-(diphenylamino)phenyl)-3-phenylpropane-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-(diphenylamino)phenyl)-3-(m-tolyl)propane-1,3-dione boron difluoride complex (2bj, 64 mg, 70%).

[0235] 1 H NMR(500MHz, CDCl3)δ7.93(d,J=9.1Hz,2H),7.89–7.80(m,2H),7.36(p,J=8.3, 7.9Hz, 6H), 7.27–7.18 (m, 2H), 6.99 (s, 4H), 6.93 (d, J = 9.1Hz, 2H), 2.39 (s, 3H). 13 CNMR (126MHz, CDCl3) δ181.0,180.0,154.4,145.4,138.9,135.1,132.6,1 31.2,130.0,128.9,128.9,126.7,126.0,125.6,122.4,118.4,92.3,21.4. 19 F NMR(471MHz, CDCl3)δ-140.68,-140.69,-140.74,-140.75.IR(KBr,cm -1 ):3417,3174,2359,1634,1401,1294,1088,990,854,762,532.

[0236] Example 57

[0237] This embodiment provides a method for preparing 1-(3-fluorophenyl)-3-(thiophen-2-yl)propane-1,3-dione boron difluoride complex (2bk)

[0238]

[0239] 3-(3-Fluorophenyl)-1-(thiophen-2-yl)propyl-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(3-fluorophenyl)-3-(thiophen-2-yl)propane-1,3-dione boron difluoride complex (2bk, 58 mg, 99%).

[0240] 1 H NMR (500MHz, CDCl3) δ8.09 (d, J = 8.6 Hz, 2H), 7.93 (d, J = 7.9 Hz, 1H), 7.81 (d, J = 9. 3Hz, 1H), 7.54 (dd, J=8.2, 3.6Hz, 3H), 7.40 (td, J=8.1, 2.3Hz, 1H), 7.13 (s, 1H). 13 CNMR (126MHz, CDCl3) δ182.8, 182.2, 162.92 (d, J = 249.4Hz), 142.5, 134.0, 130.98 (d, J = 7.9Hz), 130.1, 129.7, 124.7, 115.67 (d, J = 23.5Hz), 93.6. 19 F NMR(471MHz, CDCl3)δ-110.23,-138.95,-139.02.IR(KBr,cm -1 ):3481,3171,2360,1634,1401,1293,1088,990,857,766,536.

[0241] Example 58

[0242] This embodiment provides a method for preparing 1,3-bis(4-fluorophenyl)propane-1,3-dione boron difluoride complex (2bl)

[0243]

[0244] 1,3-bis(4-fluorophenyl)prop-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1,3-bis(4-fluorophenyl)propane-1,3-dione boron difluoride complex (2bl, 45 mg, 73%).

[0245] 1H NMR (500MHz, CDCl3) δ8.14(d,J=7.7Hz,2H),7.93(dd,J=8.7,5.9Hz,1H),7.74(t,J=7.4Hz ,1H),7.58(t,J=7.8Hz,2H),7.50(dd,J=8.1,2.3Hz,1H),7.29(s,1H),7.25–7.18(m,1H). 13 C NMR (126MHz, CDCl3) δ183.41 (d, J = 205.2Hz), 164.58 (d, J = 260.4Hz), 136.0, 133.80 (d, J = 9.6Hz) ,131.6,130.7,129.4,122.90(d,J=10.1Hz),122.37(d,J=24.9Hz),115.60(d,J=21.5Hz),98.8. 19 F NMR (471MHz, CDCl3) δ-102.62,-138.67,-138.73.

[0246] Example 59

[0247] This embodiment provides a method for preparing 1-(4-(dimethylamino)phenyl)-3-(4-ethylphenyl)propane-1,3-dione boron difluoride complex (2bm)

[0248]

[0249] 3-(4-(dimethylamino)phenyl)-1-(4-ethylphenyl)propyl-2-yn-1-one was used instead of 1,3-diphenylprop-2-yn-1-one in Example 1. Other materials and operations remained unchanged to obtain 1-(4-(dimethylamino)phenyl)-3-(4-ethylphenyl)propane-1,3-dione boron difluoride complex (2bm, 59 mg, 86%). 1 H NMR (500MHz, CDCl3) δ8.02 (dd, J=20.8, 7.9Hz, 4H), 7.32 (d, J=7.6Hz, 2H), 6.95 (s, 1 H), 6.69 (d, J = 8.3Hz, 2H), 3.14 (s, 6H), 2.73 (d, J = 7.4Hz, 2H), 1.27 (d, J = 7.8Hz, 3H). 13 C NMR (126MHz, CDCl3) δ178.13,155.12,151.04,131.80,130.50,128.42,118.29,111.33,91.23,40.09,29.70,29.06,15.09. 19FNMR(471MHz, CDCl3)δ-141.82,-141.88.

[0250] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing an O,O-boron difluoride complex, characterized in that: Under the action of a catalyst, the alkynone compound represented by formula (1) and a boron source are used as raw materials to react in a solvent to prepare the O,O-boron difluoride complex represented by formula (2). The reaction formula is as follows: Among them, R 1 is a C1-C6 alkyl group; or a substituted or unsubstituted C6-C14 aryl group; or a C4-C10 heteroaryl group; the substituted substituent is selected from one or more of a C1-C6 alkyl group, a C1-C6 alkoxy group, a halogen group, a trifluoromethyl group, a trifluoromethoxy group, a cyano group, an N,N-dimethylamino group or an N,N-diphenylamino group; when the substitution is multiple-site substitution, the substituted substituents are the same or different; R 2 is a substituted or unsubstituted C6-C14 aryl group; the substituted substituent is selected from one or more of C1-C6 alkyl, C1-C6 alkoxy, halogen, trifluoromethyl, trifluoromethoxy, N,N-dimethylamino, N,N-diphenylamino or cyano; when the substitution is multiple-site substitution, the substituted substituents are the same or different; The boron source is tetrafluoroboric acid or silver tetrafluoroborate; The catalyst is a gold catalyst and / or silver tetrafluoroborate; The molar ratio of the alkynone compound represented by formula (1), the boron source and the catalyst is 1:1-5:0.01-0.05; The gold catalyst is one or more of IPrAuCl, SIPrAuCl, IMesAuCl, SIMesAuCl, PPh3AuCl, KAuCl4 or NaAuCl4.

2. The preparation method according to claim 1, characterized in that The catalyst is a gold catalyst and silver tetrafluoroborate, and the molar ratio of the gold catalyst to silver tetrafluoroborate is 1:1-150.

3. The preparation method according to claim 1, characterized in that: The solvent is one or more of acetonitrile, toluene, tetrahydrofuran, 1,4-dioxane, fluorobenzene, ethylene glycol, isopropanol, nitrobenzene, and trifluorotoluene.

4. The preparation method according to claim 1, characterized in that The solvent is a combination of toluene and water, fluorobenzene and water, nitrobenzene and water, or trifluorotoluene and water.

5. The preparation method according to claim 1, characterized in that: The reaction temperature is 60-150°C.

6. The preparation method according to claim 1, characterized in that: The reaction temperature is 80-90°C.

7. The preparation method according to claim 1, characterized in that: The reaction time is 24 to 48 hours.

8. The preparation method according to claim 1, characterized in that: The reaction time is 30 to 40 hours.

Images