Novel generation of selenoaldehydes through stannic chloride-induced unsymmetrical C-Se bond cleavage of bis(N,N-dimethylcarbamoylseleno)methanes

Reaction of diselenoacetals A with SnCl4 afforded β-1,3,5-triselenanes through a stepwise pathway involving the generation of acylselonium ions B and selenoaldehydes C.