Peer-Reviewed Journal Details
Mandatory Fields
Heaney, F;McCarthy, T;Mahon, M;McKee, V
2005
January
Organic and Biomolecular Chemistry
Bridgehead nitrogen heterocycles which contain the quinazoline moiety - synthesis and cycloaddition of 1,2-dihydroquinazoline 3-oxides
Published
17 ()
Optional Fields
STABLE AZOMETHINE YLIDES DIMETHYL ACETYLENEDICARBOXYLATE THERMAL-DECOMPOSITION 1,4-BENZODIAZEPINES DERIVATIVES 2,3-DIHYDROISOXAZOLES REARRANGEMENT NITRONES CYCLIZATION GENERATION
3
4351
4361
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.
CAMBRIDGE
1477-0520
10.1039/b511998g
Grant Details