Synthesis of Substituted Dihydrobenzofurans via Tandem S<sub>N</sub>Ar/5-<i>Exo-Trig</i> Cyclization
作者:Maximilian Koy、Keary M. Engle、Lawrence M. Henling、Michael K. Takase、Robert H. Grubbs
DOI:10.1021/acs.orglett.5b00743
日期:2015.4.17
SNAr/5-exo-trig cyclization reaction is reported that converts N-alkyl- and -arylimines derived from o-fluorobenzaldehydes into 3-amino-2,3-dihydro-2,2-diarylbenzofurans in moderate to good yields. Diarylmethoxide coupling partners serve the dual role of nucleophile in the SNAr step and catalytic base in the cyclization step. With a subset of the substrates, a further base-induced elimination of the
据报道,串联SNAr / 5-exo-trig环化反应可将中邻氟苯甲醛的N-烷基-和-芳基嘧啶以中等至良好的产率转化为3-氨基-2,3-二氢-2,2-二芳基苯并呋喃。二芳基甲醇盐偶联伙伴在SNAr步骤中具有亲核试剂的功能,在环化步骤中具有催化碱的功能。对于部分底物,观察到了进一步的碱诱导的3-氨基-2,3-二氢-2,2-二芳基苯并呋喃被消除为酚烯胺。