Heaney, Frances and McCarthy, Tomas and Mahon, Mary and McKee, V. (2005) Bridgehead nitrogen heterocycles which contain the quinazoline moiety – synthesis and cycloaddition of 1,2-dihydroquinazoline 3-oxides. Organic & Biomolecular Chemistry, 3. pp. 4351-4361. ISSN 1477-0520

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Abstract

A novel synthesis of 1,2-disubstituted 1,2-dihydroquinazoline 3-oxides 8 and the first ever examples of 1,3-dipolar trapping of these nitrones to homonuclear dipolarophiles is described. The new dipoles 8 reacted with N-methyl maleimide, generating diastereomeric adducts 14–16. In the reaction between 8 and dimethyl acetylenedicarboxylate, primary cycloadducts 17 and/or stable rearrangement products, azomethine ylides 18, are formed depending on the substitution pattern of the dipole. The structure of 18c is unambiguously assigned by X-ray crystallographic analysis. An X-ray crystal structure determination is also presented for the cyclopropylisoxazoloquinazoline 22 formed by a [3 + 2] addition of 8a to 21, the dimethyl acetylenedicarboxylate tetramer.

Item Type:	Article
Keywords:	Bridgehead nitrogen heterocycles; quinazoline moiety; synthesis and cycloaddition; 1,2-dihydroquinazoline 3-oxides;
Academic Unit:	Faculty of Science and Engineering > Chemistry
Item ID:	4291
Depositing User:	Dr. Frances Heaney
Date Deposited:	09 Apr 2013 09:27
Journal or Publication Title:	Organic & Biomolecular Chemistry
Publisher:	Royal Society of Chemistry
Refereed:	Yes
URI:	Publisher
Use Licence:	This item is available under a Creative Commons Attribution Non Commercial Share Alike Licence (CC BY-NC-SA). Details of this licence are available here

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