Organocatalytic Enantioselective Vinylogous Michael-AIdoI Cascade for the Synthesis of Spirocyclic Compounds

Mondal, Santigopal and Mukherjee, Subrata and Yetra, Santhivardhana Reddy and Gonnade, Rajesh G and Biju, Akkattu T (2017) Organocatalytic Enantioselective Vinylogous Michael-AIdoI Cascade for the Synthesis of Spirocyclic Compounds. In: ORGANIC LETTERS, 19 (16). pp. 4367-4370.

PDF Org_Let_19-16_4367_2017.pdf - Published Version Restricted to Registered users only Download (1MB) | Request a copy

Abstract

Enantioselective synthesis of pyrazolone-fused spirocyclohexenols by the secondary amine-catalyzed cascade reaction of alpha,beta-unsaturated aldehydes with alpha-arylidene pyrazolinones is reported. This formal 3 + 3] organocascade reaction proceeds through a vinylogous Michael-aldol sequence to furnish the spiroheterocycles with three stereocenters including an all-carbon quaternary center in good yields and selectivities. The catalytic generation of alpha,beta-unsaturated iminium ions from enals and tandem dienolate/enolate formation from pyrazolinones are the key for the success of this spiroannulation reaction.

Item Type:	Journal Article
Publication:	ORGANIC LETTERS
Additional Information:	Copy right for this article belongs to the AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA
Department/Centre:	Division of Chemical Sciences > Organic Chemistry
Date Deposited:	16 Sep 2017 06:17
Last Modified:	16 Sep 2017 06:17
URI:	http://eprints.iisc.ac.in/id/eprint/57816

Actions (login required)

View Item