18151-52-5Relevant academic research and scientific papers
Thermal hydrosilylation of olefin with hydrosilane. Preparative and mechanistic aspects
Jung, Dong Euy,Han, Joon Soo,Yoo, Bok Ryul
, p. 3687 - 3692 (2011)
The reaction of trichlorosilane (1a) at 250 °C with cycloalkenes, such as cyclopentene (2a), cyclohexene (2b), cycloheptene (2c), and cyclooctene (2d), gave cycloalkyltrichlorosilanes [CnH2n-1SiCl3: n = 5 (3a), 6 (3b), 7 (3c), 8 (3d)] within 6 h in excellent yields (97-98%), but the similar reactions using methyldichlorosilane (1b) instead of 1a required a longer reaction time of 40 h and afforded cycloalkyl(methyl)dichlorosilanes [CnH2n-1SiMeCl2: n = 5 (3e), 6 (3f), 7 (3g), 8 (3h)] in 88-92% yields with 4-8% recovery of reactant 2. In large (2, 0.29 mol)-scale preparations, the reactions of 2a and 2b with 1a (0.58 mol) under the same condition gave 3a and 3b in 95% and 94% isolated yields, respectively. The relative reactivity of four hydrosilanes [HSiCl3-mMem: m = 0-3] in the reaction with 2a indicates that as the number of chlorine-substituent(s) on the silicon increases the rate of the reaction decreases in the following order: n = 3 > 2 > 1 ? 0. In the reaction with 1a, the relative reactivity of four cycloalkenes (ring size = 5-8) decreases in the following order: 2d > 2a > 2c > 2b. Meanwhile linear alkenes like 1-hexene undergo two reactions of self-isomerization and hydrosilylation with hydrosilane to give a mixture of the three isomers (1-, 2-, and 3-silylated hexanes). In this reaction, the reactivity of the terminal 1-hexene is higher than the internal 2- and 3-hexene. The redistribution of hydrosilane 1 and the polymerization of olefin 2 occurred rarely under the thermal reaction condition.
Asymmetric palladium-catalyzed hydrosilylation of styrenes using efficient chiral spiro phosphoramidite ligands
Guo, Xun-Xiang,Xie, Jian-Hua,Hou, Guo-Hua,Shi, Wen-Jian,Wang, Li-Xin,Zhou, Qi-Lin
, p. 2231 - 2234 (2007/10/03)
Asymmetric hydrosilylation of styrene derivatives with trichlorosilane in the presence of palladium complexes of chiral spiro phosphoramidites provided 1-aryl-1-silylalkanes as single regioisomers in high yields, which have been oxidized with hydrogen peroxide to give the corresponding chiral alcohols in up to 99.1% ee.
Asymmetric Hydrosilylation of 1-Alkenes Catalyzed by Palladium-MOP
Uozumi, Yasuhiro,Kitayama, Kenji,Hayashi, Tamio,Yanagi, Kazunori,Fukuyo, Emiko
, p. 713 - 722 (2007/10/02)
Asymmetric hydrosilylation of simple terminal alkenes (RCH=CH2) with trichlorosilane at 40 deg C in the presence of 1*10-3 or 1*10-4 molar amounts of palladium catalyst prepared in situ from 3-C3H5)>2 and (S)-2-diphenylphosphino-2'-methoxy-1,1'-binaphthyl ((S)-MeO-MOP) proceeded with unusual regioselectivity and with high enantioselectivity to give high yields of 2-(trichlorosilyl)alkanes together with a minor amount of 1-(trichlorosilyl)alkanes.Optically active alcohols, RCH(OH)CH3, were obtained by oxidation of the carbon-silicon bond.Regioselectivities for forming 2-silylalkanes over 1-silylalkanes and enantiomeric purities of alcohols are as follows: R=n-C4H9: 89/11, 94percent ee (R).R=n-C6H13: 93/7, 95percent ee (R).R=n-C10H21: 94/6, 95percentee (R).R=PhCH2CH2: 81/19, 97percentee (S).R=PhCH2CH2CH2: 80/20, 92percent ee (R).R=cyclo-C6H11: 66/34, 96percent ee (R).A similar hydrosilylation of 1-alkenes, 4-pentenyl benzoate and 1,5-heptadiene gave corresponding 2-alkanols of 90percent ee and 87percent ee, respectively, the ester carbonyl and the internal double bond remaining intact.
