A. P. Molchanov,T. Q. Tran, A. V. Stepakov, G. L. Starova, R. R. Kostikov
«Regioselective cycloaddition of C-carbamoylnitrones to methyl (E)-2-(2-phenylcyclopropylidene)acetate and methyl (E)-2-methylidene-3-phenylcyclopropane-1-carboxylate»
Russ. J. Org. Chem., 2014, 50, 78-82 (russ. 84-88)
N-Aryl-C-(arylcarbamoyl)nitrones regioselectively add to methyl 2-(2-phenylcyclopropylidene)-acetate and methyl 2-methylidene-3-phenylcyclopropanecarboxylate to give in each case two diastereoisomeric 5-oxa-6-azaspiro[2.4]heptane-4-carboxylates.