Highly diastereoselective 1,3-dipolar cycloaddition of nonstabilized azomethine ylides to 3-nitro-2-trihalomethyl-2H-chromenes: Synthesis of 1-benzopyrano[3,4-c]pyrrolidines

Authors :: Korotaev, V. Y.
Barkov, A. Y.
Moshkin, V. S.
Matochkina, E. G.
Kodess, M. I.
Sosnovskikh, V. Y.
Korotaev, V. Y.
Barkov, A. Y.
Moshkin, V. S.
Matochkina, E. G.
Kodess, M. I.
Sosnovskikh, V. Y.
Source :: Tetrahedron
Publication Year :: 2013
Abstract: Reactions of 3-nitro-2-trifluoro(trichloro)methyl-2H-chromenes, including 2-unsubstituted derivatives, with N-alkyl-α-amino acids (sarcosine, proline) and paraformaldehyde proceed diastereoselectively to give 1-benzopyrano[3,4-c]pyrrolidines in good yields as a result of a 1,3-dipolar cycloaddition of the intermediate nonstabilized azomethine ylide at the Δ3-bond of the chromene system. © 2013 Elsevier Ltd. All rights reserved.

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