Reactions of Achiral Nitroso Compounds

Hetero Diels-Alder reactions of nitrosoalkenes, e.g. a-nitrosostyrene, with electron-rich alkenes lead to 5,6-dihydro-4H-l,2-oxazines. The cycloadducts are obtained with excellent selectivities. These reactions proceed smoothly under mild reaction conditions at room temperature in the absence of Lewis acids. Oxazines are useful precursors for the synthesis of pyrroles and y-lactams. 

Reactions of Achiral Nitroso Compounds as Dienes with Chiral Vinylethers as Dienophiles 

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