D. Ntirampebura et L. Ghosez, Cycloadditions of 2-aza-1,3-dienes to aldehydes: a Diels-Alder strategy for the diastereoselective hydroxyalkylation of carboxylic acid derivatives, TETRAHEDR L, 40(39), 1999, pp. 7079-7082
2-Aza-1,3-dienes 1 which are readily prepared from carboxylic acids cycload
d to aldehydes to give good yields of 1,3-oxazinones 3. The cycloadditions
were highly diastereoselective in favour of the endo adducts. Hydrolysis of
1,3-oxazinones 3 stereoselectively yielded the corresponding beta-hydroxya
mides 4. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.