Sm. Sparks et al., Type 2 intramolecular nitroso Diels-Alder reaction. Synthesis and structure of bridgehead oxazinolactams, ORG LETT, 2(10), 2000, pp. 1473-1475
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The type 2 intramolecular Diels-Alder cycloaddition utilizing N-acylnitroso
dienophiles provides an efficient entry into bridged oxazinolactams. In co
ntrast to the bimolecular counterpart, the reaction is completely regiosele
ctive, Structural characterization of the cycloadducts allows for evaluatio
n of the olefin distortion and the degree of pyramidalization of the bridge
head oxazinolactam.