A new route to seleno and telluro esters by Co 2(CO) 8-mediated and -catalyzed carbonylation of diaryl diselenides and ditellurides with carbon monoxide

Abstract

Diaryl Diselenides react with CO(5–100 atm) at 100-200°C during 1–4 h in the presence of Co 2(CO) 8 to give the corresponding aryl selenocarboxylic acid esters in 21–96% yields. Similar treatment of diphenyl ditelluride gives the telluro analogues in lower yields. Didodecyl diselenide also gives the corresponding seleno ester, while esters were not produced from dibenzyl diselenide and didodecyl ditelluride. Under milder conditions (10 atm CO/125°C/1 h) the reactivity of (PhM) 2 (M  S, Se, Te) for the corresponding esters was found to be in the order Te > Se > S. The carbonylation of diaryl diselenides proceeds catalytically in Co 2(CO) 8 in the presence of triphenylphosphine. It was shown unambiguously that benzoylcobalt tetracarbonyl, which is one of the possible intermediates when aryl is phenyl, reacts smoothly with diphenyl diselenide or ditellutide to give the corresponding ester, phenyl selenobenzoate or tellurobenzoate, respectively, in a good yield.