Synthesis 2021; 53(13): 2240-2252
DOI: 10.1055/a-1384-1967
paper

Diastereoselective trans Cyclopropanation of 3-Alkylidene Oxindoles with In Situ Generated α-Diazo Carbonyls or α,β-Unsaturated Diazo Compounds

Sayan Pramanik
a   Department of Chemistry, University of Calcutta, 92 APC Road, Kolkata 700009, India
,
Suman Ray
b   Department of Chemistry, Presidency University, Kolkata 700073, India
,
Suvendu Maity
c   Department of Chemistry, R. K. Mission Residential College, Narendrapur, Kolkata 700103, India
,
Prasanta Ghosh
c   Department of Chemistry, R. K. Mission Residential College, Narendrapur, Kolkata 700103, India
,
a   Department of Chemistry, University of Calcutta, 92 APC Road, Kolkata 700009, India
› Author Affiliations
SP thanks the Council of Scientific and Industrial Research (CSIR), New Delhi, for a fellowship (SRF). We also are grateful to CAS-V, DST-FIST, and DST-PURSE Department of Chemistry, University of Calcutta, for funding as departmental projects.


Abstract

An efficient diastereoselective trans cyclopropanation of 3-alkylidene oxindoles with in situ generated α-diazo carbonyl compounds or α,β-unsaturated diazo compounds under metal-free conditions has been developed to synthesize 3-spirocyclopropyl-2-oxindole derivatives. The procedure is based on the 1,3-dipolar character of the corresponding diazo compounds under base-catalyzed conditions. The method has a wide substrate scope and uses easily available starting materials.

Supporting Information



Publication History

Received: 11 December 2020

Accepted after revision: 05 February 2021

Accepted Manuscript online:
05 February 2021

Article published online:
08 March 2021

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