Synthesis 2011(18): 2951-2958  
DOI: 10.1055/s-0030-1260155
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

Iodine-Mediated Neighboring Group Assisted Synthesis of Unsymmetrical 1,2-Diketone/Benzil Derivatives from o-(Alkynyl)benzamides

K. C. Majumdar*a,b, Inul Ansarya, Rajendra Narayan Dea, B. Roya
a Department of Chemistry, University of Kalyani, Kalyani 741235, W. B., India
b Department of Chemical Sciences, Tezpur University, Napaam, Tezpur 784024, Assam, India
e-Mail: kcm_ku@yahoo.co.in ;
Further Information

Publication History

Received 20 May 2011
Publication Date:
05 August 2011 (online)

Abstract

A facile synthesis of 1,2-diketone derivatives have been achieved from o-(alk-1-ynyl)benzamide derivatives in good to excellent yields by molecular iodine-catalyzed electrophilic reaction. The reaction proceeds via formation of an (isochromenylidene)benzenaminium intermediate formed by the intramolecular neighboring group assistance of the ortho-amide group.

1

Presently at Department of Chemical Sciences, Tezpur University, Napaam, Tezpur 784024, Assam, India.