Selective hydrogenation of 4,5-dihydro-1,3-oxazin-6-ones to carboxaldehyde derivatives; chemical differentiation between acylazetidin-2-ones and the corresponding isomeric oxazin-6-ones
Abstract
The structural ambiguity between a substituted acylazetidin-2-one and the isomeric dihydrooxazin-6-one has been resolved by chemical studies; catalytic hydrogenation of the latter leads, unexpectedly, to preferential reduction of the carbonyl group to carboxaldehyde.