Iodo-1,2,3-triazole 1-oxides

The fused oxazole derivative 100 was synthesized from 3-azido-3-deoxy-l,2 5,6-di-O-isopropylidene-a-D-allofuranose, the key final step being the reaction of methyl 3-amino-3-deoxy-5,6-0-isopropylidene-p-D-alloside with DMF dimethyl acetal. The annelated pyranoside 101 was obtained by cyclization of a branched chain hexosulose derivative, and the fused triazole-piperidinoses such as 102 were made by a radical cyclization of a 3-pyrazolo-6-iodo-sugar derivative. The spiro-isoxazohne 103 and related isomers have been synthesized by dipolar cycloadditions of mesitonitrile oxide to 2-deoxy-2-C-methyl-ene-pentonic acids, themselves available in five steps from D-mannitol. Intra-... 

Methyl benzoate is formed from the 4-ethyl-4-iodo-l-methyl-l//-l,2,4-triazole-catalysed aerobic oxidation of benzaldehyde in THE in the presence of 1,8-diazabycyclo[5.4.0]undec-7-ene (DBU) and methanol. Benzoic acid is the oxidation product if the reaction is performed in the presence of water instead of the alcohol. These reactions are not reconciled with either oxidative or oxygenative mechanism... 

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