Studies on the Reaction of 3,3,4,4-Tetraphenylthietan-2-one

Article abstract of DOI:10.1021/jo01310a019

The chemical reactivity of 3,3,4,4-tetraphenylthietan-2-one (3,3,4,4-tetraphenyl-β-thiolactone, 5) toward nucleophilic, reducing, and oxidizing reagents has been investigated.Compound 5 is relatively inert toward nucleophiles (1-butanethiol, sodium hydroxide, sodium methoxide).The only product obtained from these reactions which cannot be readily attributed to initial thermal fragmentation of the ring is tetraphenylethylene (10).Treatment of 5 with the strong reducing reagent LiAlH4 gave four products upon workup: 2,2,3,3-tetraphenyl-1-propanol (19), 2,2,3,3-tetraphenylpropyl acetate (20), 1,1,3,3-tetraphenyl-2-propanone (7), and 1,1,3-triphenyl-2-indanone (21).The substituted acetone 7 was also obtained when DIBAL was added to 5.Desulfurization experiments with Raney nickel and cobalt catalysts consistently gave 10 in varying amounts.In addition to the alkene 10, compounds 7, 21, and 2,2,3-triphenyl-4,5,6,7-tetrahydro-1-indanone (26) were also isolated with W-2 Raney nickel.Finally, oxidation of 5 with m-chloroperbenzoic acid gave the novel mixed carboxylic-sulfinic acid anhydride (32).This molecule is of particular interest in light of the previous difficulty encountered in the preparation of this class of compounds.Many of the products obtained in these reactions are not those expected based upon previous studies of β-thiolactones.Potential pathways for the origin of the compounds obtained are suggested.