Cyclic unsaturated sulfite Delta(5)-1,3-dioxa-2-thialepin-2-oxide synt
hesized from (Z)-2-butene-1,4-diol was studied in the condensation wit
h 1-heptyne. The direction of the reaction strongly depends on the con
ditions. The reaction resulted in (Z)/(E)-2-undecene-5-yn-1-ol and a b
y-product, 3-(hydroxymethyl)-1-decene-4-yne.