A Phosphine-Mediated Dearomative Skeletal Rearrangement of Dianiline Squaraine Dyes
作者:Emily P. Bacher、Kevin J. Koh、Antonio J. Lepore、Allen G. Oliver、Olaf Wiest、Brandon L. Ashfeld
DOI:10.1021/acs.orglett.1c00248
日期:2021.4.16
A phosphorus(III)-mediated dearomatization of ortho-substituted dianiline squaraine dyes results in an unusual skeletal rearrangement to provide exotic, highly conjugated benzofuranone and oxindole scaffolds bearing a C3 side chain comprised of a linear conflagration of an enol, a phosphorus ylide, and 2,4-disubstituted aniline. Employing experimental and computational analysis, a mechanistic evaluation
磷 (III) 介导的邻位取代的二苯胺方酸染料的脱芳构化导致不寻常的骨架重排,从而提供具有 C3 侧链的外来高度共轭苯并呋喃酮和羟吲哚支架,该 C3 侧链由烯醇、磷叶立德和2,4-二取代苯胺。采用实验和计算分析,机械评估揭示了对苯胺邻位取代基的酸度的显着依赖性。值得注意的是,重排加合物在存在布朗斯台德酸的情况下经历了快速和完全恢复为母方方酸。