
%0 Journal Article
%A Patroni, JJ 
%A Skelton, BW 
%A Stick, RV 
%A White, RV 
%T The reaction of methyl 4,6-O-isopropylidene-2,3-O-thiocarbonyl-&#945;-D-mannoside with methyl iodide : a synthesis of methyl &#945;-Tyveloside (methyl 3,6-dideoxy-&#945;-D-<I>arabino</I>-hexopyranoside)
%J Australian Journal of Chemistry
%D 1980/05/01
%V 33
%N 5
%P 987-999
%K 
%R https://doi.org/10.1071/CH9800987
%U https://www.publish.csiro.au/paper/CH9800987 
%X The reaction of methyl 4,6-O-isopropylidene-2,3-O-thiocarbonyl-&#945;-D- mannoside with methyl iodide gives two major products, methyl 3,6- dideoxy-3,6-diiodo-2-O-(methylthio)carbonyl-&#945;-D-altro-pyranoside and methyl 2,3-O-carbonyl-6-deoxy-6-iodo-&#945;-D-mannopyranoside, both of which lack the 4,6-O-isopropylidene grouping but contain the 6-deoxy-6-iodo function, and another minor product. One of the major products, methyl 3,6-dideoxy-3,6-diiodo-2-O-(methylthio)carbonyl-&#945;-D-altro-pyranoside, is converted into methyl &#945;-tyveloside by sequential reduction and ester removal. The incorporation of iodine at C6 is seemingly due to hydrogen iodide, and may be suppressed in the presence of N,N,N,N- tetramethylnaphthalene-1,8-diamine or propylene oxide, or by the use of 4,6-O-benzylidene-2,3-O-thiocarbonyl-&#945;-D-mannoside as substrate. Methyl iodide/propylene oxide is apparently an efficient combination for thiocarbonate (C=S) into carbonate conversion. The structure of the minor product was shown by single-crystal X-ray diffraction to be 1,6- anhydro-3-deoxy-3-iodo-2-O-(methylthio)carbonyl-&#946;-D-altropyranose. 
