Sulfonyl esters 6. Elucidation of the first sequence in the Trithioorthoformate Reaction

Abstract

Abstract:The one-pot conversion of a mercaptan and an aryl methanesulfonate into a trithioorthoformate is described.

Sulfonyl esters 7. The second and third sequences in the Trithioorthoformate Reaction

“…Scheme 1 outlines the pathway for the first sequence of the Trithioorthoformate Reaction, which produces the intermediate sulfide-sulfonate ester 2 as described earlier (2). We now disclose our findings and conclusions about the processes that transform the sulfide-sulfonate ester 2 into the trithioorthoforrnate 1.…”

“…We conclude that the carbanions derived from 4 and 12 have no effective way to reach 1 and that the Trithioorthoformate Reaction is unlikely to proceed through a dithiocarbene. In sharp contrast to these sulfone experiments, phenyl methanesulfonate produces no 1 at room temperature but converts ptolyl mercaptide anions into 1 in 40% yield at 100°C (2).…”

“…Typically, our reactions on sulfonates furnish both p-tolyl disulfide and the trithioorthoformate 1, which are eluted in immediately adjacent fractions using low-polarity solvents (e.g., see "Reaction of 2 with sodiump-tolyl mercaptide in the presence of p-chlorophenol" in ref. 2). However, elution of the products from the reaction depicted in Scheme 3 provided the disulfide and 1 separated by about 30 fractions.…”

“…[ l ] reaction was successfully rerun with sodium metal2 (vide eq. [2]), which, presumably, must react as such an agent.…”

“…The second sequence of the trithioorthoforrnate reaction The intermediacy of sulfide-sulfonate ester 2 (Scheme 1) was established after it was isolated cleanly by means of column chromatography (2). We were unable to isolate any other intermediates in this way.…”