α‐Selective Ring‐Opening Reactions of Bicyclo[1.1.0]butyl Boronic Ester with Nucleophiles
作者:Lin Guo、Adam Noble、Varinder K. Aggarwal
DOI:10.1002/anie.202011739
日期:2021.1.4
The reaction of bicyclo[1.1.0]butyl pinacol boronic ester (BCB‐Bpin) with nucleophiles has been studied. Unlike BCBs bearing electron‐withdrawing groups, which react with nucleophiles at the β‐position, BCB‐Bpin reacts with a diverse set of heteroatom (O, S, N)‐centred nucleophiles exclusively at the α‐position. Aliphatic alcohols, phenols, carboxylic acids, thiols and sulfonamides were found to be
研究了双环[1.1.0]丁基频哪醇硼酸酯(BCB-Bpin)与亲核试剂的反应。与带有吸电子基团的BCB在β位置与亲核试剂反应不同,BCB-Bpin仅与在α位置以杂原子(O,S,N)为中心的各种异核亲核反应。发现脂肪族醇,酚,羧酸,硫醇和磺酰胺是有效的亲核试剂,可轻松获得α-杂原子取代的环丁基硼酸酯。相反,位阻双磺酰胺和相关亲核试剂与BCB-Bpin在β'位置反应,生成具有高反选择性的环丙烷。讨论了选择性的起源。