Efficient synthesis of 6-membered cyclic monothiocarbonates from halohydrin and carbonyl sulfide

Abstract

We report herein an efficient method to synthesize 6-membered cyclic monothiocarbonates which are important intermediates for polymonothiocarbonate synthesis via the cycloaddition of carbonyl sulfide with 1,3-halohydrin using a low-cost base...

Direct C−H Sulfuration: Synthesis of Disulfides, Dithiocarbamates, Xanthates, Thiocarbamates and Thiocarbonates

“…[89] As shown in Scheme 5B, typical methods for preparing 1,3-oxathiolan-2-ones include: a) cyclizations of hydroxyl thiols with phosgene; [90] b) acid-assisted cyclizations of 2-hydroxyethyl thiocarbonates; [91] c) base-assisted cyclizations of imidazolide derivatives; [92] d) O,S-rearrangements of cyclic thiocarbonates; [93] e) reactions of propargylic alcohols or epoxides with carbonyl sulfide [94] or the combination of carbon monoxide and sulfur; [95] and f) base-promoted cycloadditions of carbonyl sulfide with 1,3-halohydrins. [96] Despite the significant progress made in the preparation of organic disulfides, dithiocarbamates, xanthates, thiocarbamates and thiocarbonates, most approaches suffer from one or more disadvantages such as multi-step operations, tedious preparations of highly prefunctionalized starting materials such as unstable organometallic reagents, poor atom-economy, and the involvement of expensive and hazardous metal catalysts and additives. Therefore, the development of more efficient and convenient approaches for the preparation of such compounds is still highly desirable.…”

“…As shown in Scheme 5A, reported methods for preparing benzo[ d ][1,3]oxathiol‐2‐ones include: a) cyclizations of 2‐mercaptophenol with phosgene or carbonyl sulfide; [87] b) Bu 3 N/AlCl 3 ‐promoted [3+2] cyclocondensations between phenols and chlorocarbonylsulfenyl chloride; [88] and c) thermal rearrangements of O ‐(2‐methoxyphenyl) thiocarbamates followed by intramolecular cyclizations of the resulting S ‐(2‐methoxyphenyl) thiocarbamates [89] . As shown in Scheme 5B, typical methods for preparing 1,3‐oxathiolan‐2‐ones include: a) cyclizations of hydroxyl thiols with phosgene; [90] b) acid‐assisted cyclizations of 2‐hydroxyethyl thiocarbonates; [91] c) base‐assisted cyclizations of imidazolide derivatives; [92] d) O , S ‐rearrangements of cyclic thiocarbonates; [93] e) reactions of propargylic alcohols or epoxides with carbonyl sulfide [94] or the combination of carbon monoxide and sulfur; [95] and f) base‐promoted cycloadditions of carbonyl sulfide with 1,3‐halohydrins [96] …”