Starting from mercaptoacetic acid esters of 1, 2-or 1, 3-diols and substituted acetylenes 12- and 13-membered sulfur-containing lactones as 1: 1 adducts were synthesised in yields up to 48%. The mechanism of this homolytic reaction, which is initiated by the tripropylb0rane/ oxygen system, includes generation of thiyl radicals and their addition to the triple bond of alkynes. Condensation of dihalides or ditosylates with glycols or dithiols presents the most ...
