Facile coupling of propargylic, allylic and benzylic alcohols with allylsilane and alkynylsilane, and their deoxygenation with Et3SiH, catalyzed by Bi(OTf)3 in [BMIM][BF4] ionic liquid (IL), with recycling and reuse of the IL
作者:G. G. K. S. Narayana Kumar、Kenneth K. Laali
DOI:10.1039/c2ob26046h
日期:——
substituted propargylic alcohol 1e with allyl-TMS gave the skeletally intact 1,5-enyne and a ring opened derivative as a mixture. Coupling of propargylic/allylic alcohol 1f with allyl-TMS resulted in allylation at both benzylic (2 isomers) and propargylic positions, as major and minor products respectively. The scope of this methodology for allylation of a series of allylic and benzylic alcohols was explored
烯丙基三甲基硅烷(allyl-TMS)在[BMIM] [BF 4 ]溶剂中存在10%Bi(OTf)3的条件下与炔丙醇1a-1d反应,以可观的分离产率提供相应的1,5-烯炔(87-93% ) 在室温下。Bi(OTf)3作为高级催化剂的实用性在一项调查研究中得到了证实,该研究利用多种金属三氟甲磺酸酯(Bi,Ln,Al,Yb)以及B(C 6 F 5)与烯丙基-TMS与1a偶联。3,锌(NTF 2)2和Bi(NO 3)3 ·5H 2 O.环丙基耦合取代的炔丙醇1E用烯丙基-TMS得到骨架完整的1,5-烯炔和开环衍生物的混合物。炔丙基/烯丙基醇1f与烯丙基-TMS的偶联导致分别作为主要和次要产物的苄基(2个异构体)和炔丙基位置上的烯丙基化。探索了该方法用于一系列烯丙基和苄基醇的烯丙基化的范围。用Et 3 SiH可以实现高选择性的大量炔丙基,炔丙基/烯丙基,双烯丙基,烯丙基和苄基醇的化学选择性还原,反