Cooperative catalysis of N-heterocyclic carbene and Brønsted acid for a highly enantioselective route to unprotected spiro-indoline-pyrans

Youqiang Lin; Limin Yang; Yue Deng; Guofu Zhong

doi:10.1039/c5cc02096d

Cooperative catalysis of N-heterocyclic carbene and Brønsted acid for a highly enantioselective route to unprotected spiro-indoline-pyrans

Chem Commun (Camb). 2015 May 14;51(39):8330-3. doi: 10.1039/c5cc02096d.

Authors

Youqiang Lin¹, Limin Yang, Yue Deng, Guofu Zhong

Affiliation

¹ College of Materials, Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou 310018, China. myang@hznu.edu.cn zgf@hznu.edu.cn.

PMID: 25882587
DOI: 10.1039/c5cc02096d

Abstract

A chiral cooperative catalysis of NHC and Brønsted acid for a formal [4+2] reaction of unprotected isatins and enals was developed for the direct synthesis of unprotected spiro[indoline-3,2'-pyran]-2,6'(3'H)-diones in good to excellent yields (up to 95%) with high enantioselectivities (up to >93% ee).

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Indoles / chemistry*
Methane / analogs & derivatives*
Methane / chemistry
Pentanoic Acids / chemistry
Pyrans / chemistry*
Spiro Compounds / chemistry*
Stereoisomerism

Substances

Indoles
Pentanoic Acids
Pyrans
Spiro Compounds
carbene
pivalic acid
Methane