Ketones to amides via a formal Beckmann rearrangement in 'one pot': a solvent-free reaction promoted by anhydrous oxalic acid. Possible analogy with the Schmidt reaction

Chandrasekhar, Sosale and Gopalaiah, Kovuru (2003) Ketones to amides via a formal Beckmann rearrangement in 'one pot': a solvent-free reaction promoted by anhydrous oxalic acid. Possible analogy with the Schmidt reaction. In: Tetrahedron Letters, 44 (40). pp. 7437-7439.

PDF sdarticle36.pdf - Published Version Restricted to Registered users only Download (123kB) | Request a copy

Abstract

A variety of ketones can be directly converted into the secondary amides expected from a Beckmann rearrangement of the corresponding oximes in high yield, by heating them with hydroxylamine hydrochloride and anhydrous oxalic acid at similar to 100degreesC for 4-12 h. (Aromatic aldehydes afforded mixtures of nitrile and amide.) The transformation is apparently (kinetically) driven by the coupled decomposition of oxalic acid (to CO+CO2) via the fragmentation of an intermediate oxime mono-oxalate. However, an alternative pathway, mechanistically analogous to the Schmidt reaction, is not only equally likely but may well be general for the Beckmann rearrangement.

Item Type:	Journal Article
Publication:	Tetrahedron Letters
Publisher:	Elsevier Science
Additional Information:	Copyright of this article belongs to Elsevier Science.
Keywords:	Beckmann rearrangement;ketones;one-pot;oxalic acid; oximes;Schmidt reaction;secondary amides;solvent-free.
Department/Centre:	Division of Chemical Sciences > Organic Chemistry
Date Deposited:	27 Aug 2009 06:10
Last Modified:	19 Sep 2010 04:55
URI:	http://eprints.iisc.ac.in/id/eprint/17073

Actions (login required)

View Item