The catalytic decarboxylative allylation of enol carbonates: the synthesis of enantioenriched 3-allyl-3'-aryl 2-oxindoles and the core structure of azonazine

K Naresh Babu; Souvik Pal; Arindam Khatua; Avishek Roy; Alakesh Bisai

doi:10.1039/d1ob02048j

The catalytic decarboxylative allylation of enol carbonates: the synthesis of enantioenriched 3-allyl-3'-aryl 2-oxindoles and the core structure of azonazine

Org Biomol Chem. 2021 Dec 22;20(1):127-131. doi: 10.1039/d1ob02048j.

Authors

K Naresh Babu¹, Souvik Pal¹, Arindam Khatua¹, Avishek Roy¹, Alakesh Bisai^{1

2}

Affiliations

¹ Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhauri, Bhopal - 462 066, Madhya Pradesh, India. alakesh@iiserkol.ac.in.
² Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia - 741246, West Bengal, India.

PMID: 34897364
DOI: 10.1039/d1ob02048j

Abstract

The catalytic asymmetric synthesis of 3-allyl-3'-aryl 2-oxindoles has been shown via the Pd(0)-catalyzed decarboxylative allylation of allylenol carbonates. This methodology provides access to a variety of 2-oxindole substrates (5a-v) with all-carbon quaternary stereocenters (up to 94% ee) at the pseudobenzylic position under additive-free and mild conditions. The synthetic potential of this method was shown by the asymmetric synthesis of the tetracyclic core of the diketopiparazine-based alkaloid azonazine (11).

Publication types

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