Synthesis 2009(18): 3077-3088  
DOI: 10.1055/s-0029-1217603
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

Synthesis of 2-Amino-3,4-dihydroquinazolines and Imidazo[2,1-b]quinazoline-2-ones [¹]

Amita Mishra, Sanjay Batra*
Medicinal and Process Chemistry Division, Central Drug Research Institute, PO Box 173, Lucknow 226001, India
Fax: +91(522)2623405; e-Mail: batra_san@yahoo.co.uk;
Further Information

Publication History

Received 5 May 2009
Publication Date:
10 July 2009 (online)

Abstract

A straightforward method for the synthesis of 2-amino-3,4-dihydroquinazolines from Baylis-Hillman derivatives is disclosed. The protocol involves sequential SN2 reaction of a primary amine on the Baylis-Hillman acetate derived from 2-nitrobenzaldehyde, cyanogen bromide-mediated nitrile addition, and iron-acetic acid promoted reductive cyclization. This approach is also applied to the preparation of imidazo[2,1-b]quinazoline-2-ones and imidazo[2,1-b]quinazolines in one pot.

1

CDRI Communication No. 7780.

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1

CDRI Communication No. 7780.