Synthesis of bis (1,4-disubstituted-1,2,3 triazoles) starting from diethyl galactarate

This communication reports the synthesis of a series of bis (1,4-disubstituted-1,2,3-triazoles) starting from the known (2,3,4,5) bis acetonide protected diethyl galactarate (1). Reduction of 1 with LiAlH₄ led to dioxolane 2 (90%), which upon treatment with CBr₄ gave the corresponding dibromide 3 (80%). The reaction of 3 with NaN₃ in DMF afforded the key diazide 4 (95%). From diazide 4 were obtained the bis (1,4-disubstituted-1,2,3 triazoles) 5-8 via click reactions with alkyl substituted acetylenes including triphenyltinacetylene. Physical characteristics of the new compounds including selected values¹H, ¹³C, and ¹¹⁹Sn NMR data are given.