A new general two-step methodology for the synthesis of chiral fluoro, chloro, bromo and iodo vinyl azides from carbohydrate-derived halohydrins has been developed. The anomeric alkoxyl radical fragmentation of 3-azido-2,3-dideoxy-2-halo-pyranoses under oxidative conditions with (diacetoxyiodo)benzene and iodine gave 2-azido-1,2-dideoxy-1-halo-1-iodo-alditols, which by chemoselective dehydroiodination afforded (Z,E)-2-azido-1,2-dideoxy-1-halo-4-O-formyl-pent-1-enitols in good overall yields. Preliminary thermolysis and photochemical studies of these compounds for the synthesis of hitherto unknown disubstituted 2-halo-3-alkyl-2H-azirines have also been accomplished.

This work was supported by the Research Programs No. CTQ2004-06381/BQU and CTQ2004-02367/BQU of the Ministerio de Educación y Ciencia, Spain, cofinanced with the Fondo Europeo de Desarrollo Regional (FEDER). C.R.A. thanks the Program I3P-CSIC for a fellowship.

Supporting information (experimental procedures and analytical data for all new compounds) available at: http://dx.doi.org/10.1016/j.tetlet.2007.07.190

4 pages, 2 tables, 1 scheme.-- Printed version published Oct 1, 2007.