通过不对称偕二硼烷的化学选择性氧化获得 MIDA 酰基硼酸盐的模块化和简洁方法:解锁对新型酰基硼的访问†
摘要:
酰基硼酸盐是一类非常有趣且稀有的有机硼酸盐。在温和条件下从容易获得的底物合成这些化合物并获得新型酰基硼一直具有挑战性。我们报告了一种使用不对称偕二硼烷作为关键中间体从末端炔烃/烯烃或乙烯基硼酸酯制备各种 MIDA 酰基硼酸酯的新颖而简洁的途径。该策略的高模块化和温和条件允许轻松获得具有脂肪族、芳香族以及更稀有的杂芳香族、炔基和 α,β-不饱和支架的酰基硼酸盐。据我们所知,这是首个关于双硼化学选择性氧化以及合成 α,β-不饱和酰基硼酸盐的报道。
A general and atom‐economical synthesis of 1,1‐diborylalkanes fromalkenes and a borane without the need for an additional H2 acceptor is reported for the first time. The key to our success is the use of an earth‐abundant zirconium‐based catalyst, which allows a balance of self‐contradictory reactivities (dehydrogenative boration and hydroboration) to be achieved. Our method avoids using an excess
Synthesis of Vinyl Boronates from Aldehydes by a Practical Boron–Wittig Reaction
作者:John R. Coombs、Liang Zhang、James P. Morken
DOI:10.1021/acs.orglett.5b00480
日期:2015.4.3
A highly stereoselectiveboron-Wittigreaction between stable and readily accessible 1,1-bis(pinacolboronates) and aldehydes furnishes a variety of synthetically useful di- and trisubstituted vinyl boronate esters.
Dual Functionalization of α‐Monoboryl Carbanions through Deoxygenative Enolization with Carboxylic Acids
作者:Wei Sun、Lu Wang、Chungu Xia、Chao Liu
DOI:10.1002/anie.201801679
日期:2018.5.4
1‐diborylalkanes through deoxygenative enolization with carboxylicacids was developed. 1,1‐Diborylalkanes were activated by MeLi to generate α‐monoboryl carbanions. In situ IR spectroscopy indicated an interaction between carboxylicacid and 1,1‐diborylalkane before addition of the activation reagent. Release of the active α‐monoboryl carbanion from the masked form was necessary for its reaction with carboxylate