Efficient Synthesis of Spiro[furan-3,3′-indoline] Derivatives via Reactions of Pyridinium Salts with Isatinylidene Acetoacetates
作者:Zhenming Liu、Jun Fang、Chaoguo Yan
DOI:10.1002/cjoc.201300407
日期:2013.8
An efficient synthetic procedure for the functionalizedspiro[furan‐3,3′‐indoline] derivatives was successfully developed by domino reactions of N‐phenacylpyridinium bromides or N‐ethoxycarbonylmethylenepyridinium bromide with isatinylidene acetoacetate in the presence of triethylamine in ethanol at room temperature. The mechanism included sequential Michael addition of the in situ generated pyridinium