A method for the preparation of vicinal diols by nickel-catalyzed dihydroxylation of olefins

Abstract

This invention belongs to the field of organic synthesis technology, specifically relating to a nickel-catalyzed method for preparing vicinal diols by olefin dihydroxylation. In this invention, substituted or unsubstituted styrene is dissolved in a mixed solution of acetonitrile and deionized water. Then, the oxidant tert-butyl hydroperoxide and the catalyst nickel chloride are added, and the reaction is heated and stirred. After the reaction is complete, the solvent is removed under reduced pressure, and the crude product is purified by silica gel column chromatography to obtain the product, a vicinal diol with a specific structure. This nickel-catalyzed olefin dihydroxylation reaction significantly reduces production costs and environmental pollution while ensuring reaction efficiency and selectivity, aligning with the requirements of green chemistry and sustainable development, and possessing significant scientific and industrial application value.

Description

Technical Field

[0001] This invention belongs to the field of organic synthesis technology, specifically relating to a method for preparing vicinal diols by nickel-catalyzed olefin dihydroxylation. Background Technology

[0002] vicinal diols are a class of compounds of significant value in organic synthesis, pharmaceutical chemistry, and materials science. They are not only core structural units of numerous natural products and bioactive molecules, but also widely used as key intermediates in the synthesis of polyesters, polyurethanes, surfactants, and other chemical products, playing an indispensable role in drug development and the preparation of functional materials. Therefore, developing efficient, green, and economical methods for the synthesis of vicinal diols has always been a research hotspot and focus in the field of organic synthesis.

[0003] Traditional methods for preparing vicinal diols by olefin dihydroxylation mainly rely on stoichiometric strong oxidants, such as potassium permanganate and osmium tetroxide. For example, potassium permanganate can achieve cis-dihydroxylation of olefins under dilute alkaline conditions by forming cyclic manganese ester intermediates. However, this reaction condition is quite demanding, requiring strict control of pH and reaction temperature, and it easily generates large amounts of toxic metal salt waste, causing serious environmental pollution. Although the Criegee reaction (osmium tetroxide oxidation) has high selectivity and is widely used for the structural determination of complex molecules such as steroidal compounds, osmium tetroxide is expensive and extremely toxic. Furthermore, the residual osmium reagent needs to be treated with a reducing agent after the reaction, which not only increases production costs but also poses significant safety and environmental risks.

[0004] To address the shortcomings of traditional methods, transition metal-catalyzed olefin dihydroxylation reactions have gradually developed. Systems using ruthenium, palladium, and iron as catalysts have been reported, improving reaction efficiency and selectivity to some extent. However, these methods mostly rely on expensive metal catalysts, resulting in high costs, and some reactions still require stoichiometric amounts of strong oxidants, leading to low atom economy. Furthermore, for some unactivated olefins, existing catalytic systems often exhibit poor catalytic performance, demanding reaction conditions and making it difficult to balance product yield and selectivity, thus limiting their large-scale application in industrial production.

[0005] In recent years, with the deepening of the concept of green chemistry, the development of metal-free or inexpensive metal catalysts for olefin dihydroxylation has become a research trend. The introduction of novel catalytic modes such as electrochemical catalysis and photocatalysis has provided new ideas for the synthesis of vicinal diols, but these technologies are still in the laboratory research stage and face challenges such as complex reaction systems, high equipment requirements, and difficulties in scale-up.

[0006] Nickel, as a relatively abundant and inexpensive transition metal, exhibits unique reactivity and selectivity in the field of organocatalysis. Developing nickel-catalyzed olefin dihydroxylation reactions holds promise for significantly reducing production costs and environmental pollution while maintaining reaction efficiency and selectivity, aligning with the requirements of green chemistry and sustainable development. However, current research reports on nickel-catalyzed olefin dihydroxylation to prepare vicinal diols are limited, and there are still many shortcomings regarding the applicability of the reaction system and the clarity of the catalytic mechanism. Therefore, developing a highly efficient, mild, and universally applicable nickel-catalyzed method for olefin dihydroxylation to prepare vicinal diols has significant scientific and industrial application value. Summary of the Invention

[0007] To overcome the shortcomings of the prior art, this invention provides a nickel-catalyzed method for preparing vicinal diols by olefin dihydroxylation. While ensuring reaction efficiency and selectivity, it significantly reduces production costs and environmental pollution, aligning with the requirements of green chemistry and sustainable development, and possessing significant scientific and industrial application value.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows: This invention provides a method for preparing vicinal diols by nickel-catalyzed dihydroxylation of olefins, comprising the following steps: Substituted or unsubstituted styrene was dissolved in a mixed solution of acetonitrile and deionized water. Then, tert-butyl hydroperoxide (an oxidant) and nickel chloride (a catalyst) were added, and the mixture was heated and stirred. After the reaction was completed, the solvent was removed under reduced pressure. The crude product was then purified by silica gel column chromatography to obtain the product, which is a vicinal diol with a specific structure.

[0009] The reaction equation for this invention is as follows: Furthermore, the substituted or unsubstituted styrene is any one of the following structural formulas: .

[0010] Furthermore, the volume ratio of acetonitrile to deionized water is 4:1.

[0011] Furthermore, the amount of the oxidant tert-butyl hydroperoxide is 50%-100% of the molar amount of substituted or unsubstituted styrene.

[0012] Furthermore, the amount of nickel chloride catalyst used is 10%-20% of the molar amount of substituted or unsubstituted styrene.

[0013] Furthermore, the heating and stirring reaction is carried out at a temperature of 80-90°C for 18-24 hours.

[0014] Compared with the prior art, the beneficial effects of the present invention are: This invention involves dissolving substituted or unsubstituted styrene in a mixed solution of acetonitrile and deionized water, then adding the oxidant tert-butyl hydroperoxide and the catalyst nickel chloride. The reaction is heated and stirred. After the reaction is complete, the solvent is removed under reduced pressure, and the crude product is purified by silica gel column chromatography to obtain the product, a vicinal diol with a specific structure, in a yield of up to 76%. This nickel-catalyzed olefin dihydroxylation reaction significantly reduces production costs and environmental pollution while ensuring reaction efficiency and selectivity, aligning with the requirements of green chemistry and sustainable development, and possessing significant scientific and industrial application value. Detailed Implementation

[0015] The specific embodiments of the present invention will be further described below. It should be noted that these descriptions are for the purpose of aiding understanding the present invention, but do not constitute a limitation thereof. Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0016] Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods, and the experimental materials used in the following embodiments are all available through conventional commercial channels.

[0017] Example 1: A method for preparing vicinal diol 2a by nickel-catalyzed olefin dihydroxylation 0.5 mmol of styrene was dissolved in 2 mL of a mixed solution of acetonitrile and deionized water (the volume ratio of acetonitrile to deionized water was 4:1). Then, 0.25 mmol of tert-butyl hydroperoxide and 0.05 mmol of NiCl2 were added. The mixture was stirred at 80 °C for 18 h. After the reaction was completed, the solvent was removed under reduced pressure. The crude product was then purified by silica gel column chromatography to obtain a light yellow oily product 2a with a yield of 65%.

[0018] The NMR data for compound 2a are as follows: 1H NMR (400 MHz, CDCl3) δ 7.42 – 7.24 (m, 5H), 4.77 (dd, J = 8.3, 3.1Hz, 1H), 3.78 (s, 2H), 3.69 (dd, J = 11.4, 2.8 Hz, 1H), 3.62 (dd, J = 11.4,8.5 Hz, 1H). 13 C NMR (101 MHz, CDCl3) δ 140.50, 128.49, 127.90, 126.11, 74.74, 68.01.

[0019] Example 2: A method for preparing vicinal diol 2b by nickel-catalyzed olefin dihydroxylation The difference between Example 2 and Example 1 is that in Example 2, compound 1b is used instead of styrene. The structural formula of compound 1b is: The structural formula of the synthesized compound 2b is: Compound 2b is a pale yellow oil with a yield of 74%.

[0020] The NMR detection data of compound 2b are as follows: 1 H NMR (400 MHz, CDCl3) δ 7.27 (d, J = 8.6 Hz, 2H), 6.89 (d, J = 8.6Hz, 2H), 4.75 (dd, J = 8.0, 3.2 Hz, 1H), 3.80 (s, 3H), 3.66 (ddd, J = 19.6,11.2, 5.5 Hz, 2H), 3.08 (s, 2H). 13 C NMR (101 MHz, CDCl3) δ 159.31, 132.65, 127.37, 113.91, 74.31, 68.03, 55.29.

[0021] Example 3: A method for preparing vicinal diol 2c by nickel-catalyzed olefin dihydroxylation The difference between Example 3 and Example 1 is that in Example 3, compound 1c is used instead of styrene. The structural formula of compound 1c is: The structural formula of the synthesized compound 2c is: Compound 2c is a pale yellow oil with a yield of 72%.

[0022] The NMR detection data of compound 2c are as follows: 1H NMR (400 MHz, CDCl3) δ 7.25 (d, J = 8.4 Hz, 2H), 6.97 (d, J = 8.4Hz, 2H), 4.77 (d, J = 5.2 Hz, 1H), 3.73 (d, J = 10.1 Hz, 1H), 3.67 – 3.56 (m,1H), 2.78 (s, 2H), 1.35 (s, 9H). 13 C NMR (101 MHz, CDCl3) δ 155.05, 135.33, 126.70, 124.15, 78.67, 74.37, 68.01, 28.83.

[0023] Example 4: A method for preparing vicinal diol 2d by nickel-catalyzed olefin dihydroxylation The difference between Example 4 and Example 1 is that in Example 4, compound 1d is used instead of styrene. The structural formula of compound 1d is: The structural formula of the synthesized compound 2d is: Compound 2d is a pale yellow oil with a yield of 76%.

[0024] The NMR data for compound 2d are as follows: 1 H NMR (400 MHz, CDCl3) δ 7.21 (d, J = 8.0 Hz, 2H), 7.14 (d, J = 7.9Hz, 2H), 4.74 (dd, J = 8.1, 2.8 Hz, 1H), 4.00 (s, 2H), 3.71 – 3.53 (m, 2H),2.35 (s, 3H). 13 C NMR (101 MHz, CDCl3) δ 137.52, 130.14, 129.14, 126.08, 74.61, 68.01, 21.14.

[0025] Example 5: A method for preparing vicinal diol 2e by nickel-catalyzed olefin dihydroxylation The difference between Example 5 and Example 1 is that in Example 5, compound 1e is used instead of styrene, and the structural formula of compound 1e is: The structural formula of the synthesized compound 2e is: Compound 2e is a pale yellow oil with a yield of 70%.

[0026] The NMR detection data for compound 2e are as follows: 1H NMR (400 MHz, CDCl3) δ 7.48 – 7.38 (m, 2H), 7.33 (d, J = 8.2 Hz, 2H), 4.83 (dd, J = 8.0, 3.7 Hz, 1H), 3.79 (dd, J = 11.3, 3.7 Hz, 1H), 3.71(dd, J = 11.3, 8.0 Hz, 1H), 1.34 (s, 9H). 13 C NMR (101 MHz, CDCl3) δ 151.09, 137.49, 125.84, 125.51, 74.52, 68.02, 34.57, 31.33.

[0027] Example 6: A method for preparing vicinal diol 2f by nickel-catalyzed olefin dihydroxylation The difference between Example 6 and Example 1 is that in Example 6, compound 1f is used instead of styrene, and the structural formula of compound 1f is: The structural formula of the synthesized compound 2f is: Compound 2f is a pale yellow oil with a yield of 63%.

[0028] The NMR data for compound 2f are as follows: 1 H NMR (400 MHz, DMSO) δ 7.65 (dd, J = 5.2, 3.3 Hz, 2H), 7.61 (d, J =8.3 Hz, 2H), 7.50 – 7.40 (m, 4H), 7.39 – 7.32 (m, 1H), 5.28 (d, J = 4.3 Hz,1H), 4.75 (t, J = 5.8 Hz, 1H), 4.59 (dd, J = 10.3, 5.8 Hz, 1H), 3.47 (t, J =5.9 Hz, 2H). 13 C NMR (101 MHz, DMSO) δ 143.19, 140.64, 139.20, 129.37, 127.69, 127.37, 127.04, 126.64, 74.01, 67.86.

[0029] Example 7: A method for preparing 2g of vicinal diol by nickel-catalyzed olefin dihydroxylation The difference between Example 7 and Example 1 is that in Example 7, compound 1g is used instead of styrene, and the structural formula of compound 1g is: The structural formula of the synthesized compound 2g is: The compound, 2g, is a pale yellow oil with a yield of 60%.

[0030] The NMR detection data of compound 2g are as follows: 1 H NMR (400 MHz, CDCl3) δ 7.37 – 7.26 (m, 2H), 7.11 – 6.98 (m, 2H), 4.78 (dd, J = 8.4, 3.2 Hz, 1H), 3.70 (dd, J = 11.5, 3.3 Hz, 1H), 3.60 (dd, J= 11.4, 8.5 Hz, 1H), 3.30 (s, 9H). 13 C NMR (101 MHz, CDCl3) δ 162.40 (d, J =246.1 Hz), 136.16 (d, J = 3.0 Hz), 127.74 (d, J = 8.1 Hz), 115.38 (d, J =21.4 Hz), 74.06, 67.96. 19 F NMR (376 MHz, CDCl3) δ -114.34.

[0031] Example 8: A method for preparing vicinal diols by nickel-catalyzed olefin dihydroxylation over 2 hours The difference between Example 8 and Example 1 is that in Example 8, compound 1h is used instead of styrene, and the structural formula of compound 1h is: The structural formula of the synthesized compound 2h is: The compound was a pale yellow oil with a yield of 64% after 2 hours.

[0032] The NMR data of compound 2h are as follows: 1 H NMR (400 MHz, CDCl3) δ 7.30 (d, J = 8.5 Hz, 2H), 7.23 (d, J = 8.4Hz, 2H), 4.74 (dd, J = 8.4, 3.1 Hz, 1H), 3.67 (dd, J = 11.5, 3.2 Hz, 1H),3.56 (dd, J = 11.5, 8.5 Hz, 1H). 13 C NMR (101 MHz, CDCl3) δ 138.84, 133.69, 128.67, 127.43, 74.03, 67.81.

[0033] Example 9: A method for preparing vicinal diol 2i by nickel-catalyzed olefin dihydroxylation The difference between Example 9 and Example 1 is that in Example 9, compound 1i is used instead of styrene. The structural formula of compound 1i is: The structural formula of the synthesized compound 2i is: Compound 2i is a pale yellow oil with a yield of 62%.

[0034] The NMR detection data of compound 2i are as follows: 1 H NMR (400 MHz, CDCl3) δ 7.26 (dd, J = 13.3, 5.7 Hz, 1H), 7.15 (dd,J = 17.9, 6.6 Hz, 3H), 4.78 (dd, J = 8.2, 2.9 Hz, 1H), 3.79 – 3.70 (m, 1H), 3.70 – 3.60 (m, 1H), 3.12 (s, 2H), 2.36 (s, 3H). 13 C NMR (101 MHz, CDCl3) δ140.43, 138.20, 128.71, 128.43, 126.76, 123.13, 74.75, 68.08, 21.44.

[0035] Example 10: A method for preparing vicinal diol 2j by nickel-catalyzed olefin dihydroxylation The difference between Example 10 and Example 1 is that in Example 10, compound 1j is used instead of styrene, and the structural formula of compound 1j is: The structural formula of the synthesized compound 2j is: Compound 2j is a pale yellow oil with a yield of 65%.

[0036] The NMR detection data of compound 2j are as follows: 1 H NMR (400 MHz, CDCl3) δ 7.33 (td, J = 8.0, 5.8 Hz, 1H), 7.12 (dd, J= 11.3, 4.8 Hz, 2H), 7.06 – 6.93 (m, 1H), 4.84 (dd, J = 8.1, 3.2 Hz, 1H), 3.78 (dd, J = 11.3, 3.1 Hz, 1H), 3.64 (dd, J = 11.3, 8.2 Hz, 1H), 2.76 (s, 2H). 13C NMR (101 MHz, CDCl3) δ 162.96 (d, J = 246.2 Hz), 143.11 (d, J = 6.7Hz), 130.07 (d, J = 8.1 Hz), 121.61 (d, J = 2.9 Hz), 114.82 (d, J = 21.2 Hz),113.07 (d, J = 22.2 Hz), 74.05, 67.88. 19 F NMR (376 MHz, CDCl3) δ -112.61.

[0037] Example 11: A method for preparing vicinal diol 2k by nickel-catalyzed olefin dihydroxylation The difference between Example 11 and Example 1 is that in Example 11, compound 1k is used instead of styrene, and the structural formula of compound 1k is: The structural formula of the synthesized compound 2k is: Compound 2k is a pale yellow oil with a yield of 58%.

[0038] The NMR detection data for compound 2k are as follows: 1 H NMR (400 MHz, CDCl3) δ 7.51 (s, 1H), 7.42 (d, J = 7.6 Hz, 1H), 7.23 (dt, J = 15.3, 7.7 Hz, 2H), 4.76 (d, J = 7.3 Hz, 1H), 3.72 (d, J = 11.5 Hz,1H), 3.65 – 3.55 (m, 1H), 3.45 (s, 2H). 13 C NMR (101 MHz, CDCl3) δ 142.78, 130.99, 130.11, 129.18, 124.71, 122.65, 73.99, 67.79.

[0039] Example 12: A method for preparing vicinal diol 2l by nickel-catalyzed olefin dihydroxylation The difference between Example 12 and Example 1 is that in Example 12, compound 11 is used instead of styrene. The structural formula of compound 11 is: The structural formula of the synthesized compound 2l is: Compound 2l is a pale yellow oil with a yield of 60%.

[0040] The NMR detection data of compound 2l are as follows: 1H NMR (400 MHz, CDCl3) δ 7.54 – 7.44 (m, 1H), 7.28 – 7.23 (m, 1H), 7.24 – 7.19 (m, 1H), 7.17 (d, J = 7.0 Hz, 1H), 5.08 (dd, J = 8.4, 3.2 Hz,1H), 3.74 (dd, J = 11.5, 3.1 Hz, 1H), 3.63 (dd, J = 11.4, 8.5 Hz, 1H), 2.41(s, 2H), 2.36 (s, 3H). 13 C NMR (101 MHz, CDCl3) δ 138.45, 134.76, 130.44, 127.74, 126.31, 125.65, 71.46, 66.92, 19.03.

[0041] Example 13: A method for preparing vicinal diol 2m by nickel-catalyzed olefin dihydroxylation The difference between Example 13 and Example 1 is that in Example 13, compound 1m is used instead of styrene. The structural formula of compound 1m is: The structural formula of the synthesized compound 2m is: Compound 2m is a pale yellow oil with a yield of 52%.

[0042] The NMR data for compound 2m are as follows: 1 H NMR (400 MHz, CDCl3) δ 7.62 (dd, J = 7.7, 1.5 Hz, 1H), 7.38 – 7.30(m, 2H), 7.25 (td, J = 7.6, 1.7 Hz, 1H), 5.27 (dd, J = 7.9, 3.0 Hz, 1H), 3.92(dd, J = 11.4, 3.1 Hz, 1H), 3.60 (dd, J = 11.4, 7.9 Hz, 1H), 2.09 (s, 2H). 13 CNMR (101 MHz, CDCl3) δ 137.83, 131.94, 129.44, 128.96, 127.58, 127.10, 71.42, 66.23.

[0043] Example 14: A method for preparing vicinal diol 2n by nickel-catalyzed olefin dihydroxylation The difference between Example 14 and Example 1 is that in Example 14, compound 1n is used instead of styrene. The structural formula of compound 1n is: The structural formula of the synthesized compound 2n is: Compound 2n is a pale yellow oil with a yield of 55%.

[0044] The NMR detection data of compound 2n are as follows: 1 H NMR (400 MHz, DMSO) δ 7.55 (ddd, J = 7.9, 4.5, 1.4 Hz, 2H), 7.47– 7.32 (m, 1H), 7.19 (td, J = 7.7, 1.7 Hz, 1H), 5.49 (s, 1H), 4.86 (dd, J =7.5, 3.3 Hz, 1H), 3.51 (dd, J = 11.2, 3.4 Hz, 1H), 3.30 (dd, J = 11.2, 7.5Hz, 1H). 13 C NMR (101 MHz, DMSO) δ 142.30, 132.49, 129.38, 129.05, 128.03, 122.02, 73.39, 66.26.

[0045] Example 15: A method for preparing vicinal diol 2o by nickel-catalyzed olefin dihydroxylation The difference between Example 15 and Example 1 is that in Example 15, compound 1o is used instead of styrene, and the structural formula of compound 1o is: The structural formula of the synthesized compound 2o is: Compound 2o is a pale yellow oil with a yield of 57%.

[0046] The NMR detection data of compound 2o are as follows: 1 H NMR (400 MHz, DMSO) δ 7.96 – 7.83 (m, 4H), 7.58 – 7.42 (m, 3H), 5.38 (d, J = 4.2 Hz, 1H), 4.77 (t, J = 5.8 Hz, 1H), 4.71 (dd, J = 10.3, 5.9Hz, 1H), 3.53 (t, J = 5.9Hz, 2H). 13C NMR (101 MHz, DMSO) δ 141.57, 133.24, 132.76, 128.15, 127.92, 127.71, 126.36, 125.93, 125.46, 125.13, 74.38, 67.83.

[0047] Example 16: A method for preparing vicinal diol 2p by nickel-catalyzed olefin dihydroxylation The difference between Example 16 and Example 1 is that in Example 16, compound 1p is used instead of styrene. The structural formula of compound 1p is: The structural formula of the synthesized compound 2p is: Compound 2p is a pale yellow oil with a yield of 64%.

[0048] The NMR detection data for compound 2p are as follows: 1 H NMR (400 MHz, CDCl3) δ 7.29 (s, 1H), 7.07 – 6.96 (m, 2H), 5.03 (dd, J = 8.7, 3.0 Hz, 1H), 3.93 (s, 2H), 3.68 (dd, J = 11.7, 3.1 Hz, 1H), 3.59 (dd, J = 11.6, 8.6 Hz, 1H), 2.32 (s, 3H), 2.28 (s, 3H). 13 C NMR (101 MHz, CDCl3) δ 138.24, 135.69, 131.52, 130.32, 128.33, 126.29, 71.58, 66.99, 21.09, 18.53.

[0049] Example 17: A method for preparing vicinal diol 2q by nickel-catalyzed olefin dihydroxylation The difference between Example 17 and Example 1 is that in Example 17, compound 1q is used instead of styrene, and the structural formula of compound 1q is: The structural formula of the synthesized compound 2q is: Compound 2q is a pale yellow oil with a yield of 49%.

[0050] The NMR detection data of compound 2q are as follows: 1H NMR (400 MHz, CDCl3) δ 6.85 (s, 2H), 5.28 (dd, J = 9.9, 3.8 Hz, 1H), 3.98 (dd, J = 11.5, 9.9 Hz, 1H), 3.63 (dd, J = 11.5, 3.7 Hz, 1H), 2.47 (s, 2H), 2.42 (s, 6H), 2.27 (s, 3H). 13 C NMR (101 MHz, CDCl3) δ 137.21, 136.66, 132.47, 130.19, 72.64, 64.63, 20.77.

[0051] Example 18: A method for preparing vicinal diol 2r by nickel-catalyzed olefin dihydroxylation The difference between Example 18 and Example 1 is that in Example 18, compound 1r is used instead of styrene, and the structural formula of compound 1r is: The structural formula of the synthesized compound 2r is: Compound 2r is a pale yellow oil with a yield of 54%.

[0052] The NMR data for compound 2r are as follows: 1 H NMR (400 MHz, CDCl3) δ 7.51 – 7.43 (m, 4H), 7.37 (t, J = 7.6 Hz, 4H), 7.33 – 7.25 (m, 2H), 4.19 (s, 2H), 1.92 (s, 2H). 13 C NMR (101 MHz, CDCl3)δ 143.81, 128.44, 127.47, 126.40, 78.57, 69.41.

[0053] Example 19: A method for preparing vicinal diol 2s by nickel-catalyzed olefin dihydroxylation The difference between Example 19 and Example 1 is that in Example 19, compound 1s is used instead of styrene, and the structural formula of compound 1s is: The structural formula of the synthesized compound 2s is: Compound 2S is a pale yellow oil with a yield of 63%.

[0054] The NMR data for compound 2s are as follows: 1H NMR (400 MHz, CDCl3) δ 7.49 – 7.20 (m, 9.5H), 4.67 (d, J = 4.0 Hz,1H), 4.33 (d, J = 7.5 Hz, 0.9H), 4.06 – 3.94 (m, 1H), 3.88 – 3.75 (m, 0.9H), 3.16 (s, 3.8H), 1.05 (d, J = 6.4 Hz, 2.7H), 1.02 (d, J = 6.3 Hz, 3H). 13 C NMR(101 MHz, CDCl3) δ 141.08, 140.38, 128.48, 128.30, 128.08, 127.70, 126.92,126.63, 79.51, 77.35, 72.22, 71.38, 18.74, 16.92.

[0055] Example 20: A method for preparing 2t of vicinal diol by nickel-catalyzed olefin dihydroxylation The difference between Example 20 and Example 1 is that in Example 20, compound 1t is used instead of styrene, and the structural formula of compound 1t is: The structural formula of the synthesized compound 2t is: Compound 2t is a pale yellow oil with a yield of 57%.

[0056] The NMR data for compound 2t are as follows: 1 H NMR (400 MHz, CDCl3) δ 7.41 (d, J = 7.4 Hz, 2H), 7.35 (t, J = 7.5Hz, 2H), 7.28 (t, J = 3.6 Hz, 1H), 6.72 (d, J = 16.0 Hz, 1H), 6.23 (dd, J =16.0, 6.3 Hz, 1H), 4.46 (dd, J = 10.0, 6.6 Hz, 1H), 3.78 (dd, J = 11.2, 3.5Hz, 1H), 3.63 (dd, J = 11.2, 7.3 Hz, 1H), 2.38 (s, 1H), 2.15 (s, 1H). 13 C NMR (101 MHz, CDCl3) δ 136.29, 132.23, 128.63, 127.96, 127.71, 126.54, 73.21, 66.49.

[0057] The embodiments of the present invention have been described in detail above, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and these variations still fall within the protection scope of the present invention.

Claims

1. A process for the production of an ortho-diol by nickel-catalyzed dihydroxylation of an olefin, characterized in that, Includes the following steps: Substituted or unsubstituted styrene was dissolved in a mixed solution of acetonitrile and deionized water. Then, tert-butyl hydroperoxide (an oxidant) and nickel chloride (a catalyst) were added, and the mixture was heated and stirred. After the reaction was completed, the solvent was removed under reduced pressure. The crude product was then purified by silica gel column chromatography to obtain the product, which is a vicinal diol with a specific structure.

2. The process for the preparation of vicinal diols by nickel catalyzed dihydroxylation of an olefin according to claim 1, characterized in that, The substituted or unsubstituted styrene is any one of the following structural formulas: 。 3. The process for the preparation of vicinal diols by nickel catalyzed dihydroxylation of an olefin according to claim 1, characterized in that, The volume ratio of acetonitrile to deionized water is 4:

1.

4. The method for preparing vicinal diol by nickel-catalyzed olefin dihydroxylation according to claim 1, characterized in that, The amount of the oxidant tert-butyl hydroperoxide is 50%-100% of the molar amount of substituted or unsubstituted styrene.

5. The method for preparing vicinal diol by nickel-catalyzed olefin dihydroxylation according to claim 1, characterized in that, The amount of the catalyst nickel chloride is 10%-20% of the molar amount of substituted or unsubstituted styrene.

6. The method for preparing vicinal diol by nickel-catalyzed olefin dihydroxylation according to claim 1, characterized in that, The heating and stirring reaction is carried out at a temperature of 80-90℃ for 18-24 hours.

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