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Title: C–H functionalization of indole with diazoacetate catalyzed by a CCC-NHC Ir (III) dimer complex
The first catalytic application of a CCC-NHC pincer Ir (III) dimer complex for the C – H functionalization of N-methylindoles with a-aryl-a-diazoacetates at the C-3 position is reported herein. The Ir pincer dimer complex was used as a catalyst at 3 mol% loading. The best reaction conditions involved a combination of catalyst and substrates in a specific order. It resulted in the activation of the C–H bond with the formation of a new C–C bond to generate a-aryl-a-indolyl acetates with more than 99% conversion at room temperature without requiring any additives. Isolated yields of 84–97% were obtained for a range of substrates. Under these catalytic conditions, the unprotected N–H indoles did not react with a-aryl-a-diazoacetate. These catalytic conditions provided an efficient synthetic route to the synthesis of a-aryl-a-indolyl acetates.  more » « less
Award ID(s):
1827686
PAR ID:
10493372
Author(s) / Creator(s):
;
Publisher / Repository:
Elsevier Ltd.
Date Published:
Journal Name:
Tetrahedron Letters
Volume:
125
Issue:
C
ISSN:
0040-4039
Page Range / eLocation ID:
154610
Subject(s) / Keyword(s):
Pincer complex C–C bond formation CCC-NHC C–H functionalization Catalysis N-heterocyclic carbene
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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