Pd-Catalyzed Asymmetric Annulative Dearomatization of Phenols for Regio- and Enantioselective Synthesis of Spirocyclohexadienones
作者:Hui-Lin Mao、Yu-Xin Wang、Xue Wang、Hai-Ying Wang、Wen-Juan Hao、Bo Jiang
DOI:10.1021/acs.orglett.3c02051
日期:2023.8.18
A palladium-catalyzed asymmetric annulative dearomatization of phenols with butene dicarbonate is reported, enabling twofold decarboxylative allylation to regioselectively produce a range of spirocyclohexadienones with 29–95% yields and 74–99% ee. A catalytic dearomative formal [4 + 2] cyclization of 1,1′-biphenyl-2,4′-diols delivered spiro[chromane-4,1′-cyclohexane]-2′,5′-dien-4′-ones with high enantioselectivity
据报道,钯催化的苯酚与丁烯二碳酸酯的不对称环环脱芳构化反应能够实现双重脱羧烯丙基化,从而区域选择性地产生一系列螺环己二酮,产率为 29-95%,ee 为 74-99%。1,1'-联苯-2,4'-二醇的催化脱芳香形式[4 + 2]环化生成螺[苯并二氢吡喃-4,1'-环己烷]-2',5'-二烯-4'-酮高对映选择性,而对映体富集的螺[环己烷-1,4'-喹啉]-2,5-二烯-4-酮是从2'-氨基-[1,1'-联苯]-4-醇开始生成的,为1, 4-双亲核试剂。