A chemoenzymatic methodology has been developed using indium-mediated allylation of heterocyclic aldehydes under aqueous conditions followed by Pseudomonas cepacia lipase-catalyzed enantioselective acylation of racemic homoallylic and homopropargylic alcohols in organic media. It is observed that the lipase immobilized on ceramic particles (PS-C Amano II) catalyzes the resolution in a highly enantioselective
The first facile and efficient acid-catalyzed direct coupling of a wide range of unprotected 2,3-allenols with arylphosphine oxides was developed, offering a general, one-step approach for the synthesis of structurally diverse γ-ketophosphine oxides accompanied by concurrent C—P/C═Obondformation with remarkable functional group tolerance and complete atom-economy under metal- and additive-free conditions
开发了第一个简便而有效的酸催化的直接方法,将多种未保护的2,3-烯醇与芳基膦氧化物直接偶联,为合成结构多样的γ-酮膦氧化物同时存在C- P /C═O键的形成具有出色的官能团耐受性,并且在无金属和无添加剂的条件下具有完整的原子经济性。机理研究表明,这种转化涉及重排和磷-迈克尔反应。
Cu-Catalyzed Synthesis of 2-Silyl-1,3-butadienes from Allenols and Applications to One-Pot Synthesis of Tetrasubstituted Arylsilanes
chemo- and stereoselective method for the synthesis of (E)-2-silyl-1,3-butadienes from a broad range of allenols using mild Si–B reagents is reported in this study. Our protocol required a short reaction time at ambient temperature to produce the desired dienes in high yields. Synthetic applications are highlighted by the one-potsynthesis of tetrasubstituted arylsilanes from allenols as well as the
本研究报道了一种铜催化化学和立体选择性方法,使用温和的 Si-B 试剂从多种联烯醇合成 ( E )-2-甲硅烷基-1,3-丁二烯。我们的方案需要在环境温度下进行短反应时间才能以高产率产生所需的二烯。从联烯醇一锅合成四取代芳基硅烷以及 C-Si 键的进一步功能化突出了合成应用。
Allenylic Carbonates in Enantioselective Iridium-Catalyzed Alkylations
作者:David A. Petrone、Mayuko Isomura、Ivan Franzoni、Simon L. Rössler、Erick M. Carreira
DOI:10.1021/jacs.8b01416
日期:2018.4.4
products obtained was highlighted in a variety of stereoselective transition metal-catalyzed difunctionalization reactions. Furthermore, a combination of experimental and theoretical studies provide support for a putative reactionmechanism wherein enantiodetermining C-C coupling occurs via nucleophilic attack on a highly planarized aryl butadienylium π-system that is coordinated to the Ir center in an η2-fashion