Combined Use of Diphenyltin Sulfide or Lawesson’s Reagent and Silver Perchlorate as Effective Catalyst Systems in Aldol Reaction

Catalytic aldol reactions of several aldehydes with trimethylsilyl enol ethers are effectively performed by combined use of diphenyltin sulfide (Ph2Sn=S) and silver perchlorate (AgClO4) or Lawesson’s reagent (2,4-bis(4-methoxyphenyl)-1,3-dithia-2,4-diphosphetane-2,4-disulfide) and silver perchlorate under mild conditions.