Oxidation of Thiols with IBX or DMP: One-Pot Access to Thiosulfonates or 2-Iodobenzoates and Applications in Functional Group Transformations

Abstract

o-Iodoxybenzoic acid (IBX) and Dess−Martin periodinane (DMP) are employed for thiol to thiosulfonate conversion at rt. DMP is better than IBX in terms of reaction rate, conversion, and required equivalents. IBX-mediated oxidation of benzyl thiols produced thiosulfonates, whereas DMP afforded O-benzyl esters. The one-pot conversion of a thiol to an ester is unprecedented; this atom-economic transformation has potential for functional group transformations (FGTs), e.g., an alcohol and an aldehyde are accessed from benzyl thiol.

Kinetic Studies on Ruthenium(III) Chloride‐Catalyzed Oxidation of Benzyl and Homobenzyl Alcohols Using Cerium(IV) Sulfate under Acidic Medium

“…Benzaldehyde [11c] . Colorless liquid; 1 H NMR (CDCl 3 , 500 MHz) δ 7.50 (t, J =7.5 Hz, J =1.5 Hz, 2H), 7.59 (tt, J =7.5 Hz, J =1.5 Hz, 1H), 7.84 (dd, J =7.0 Hz, J =1.5 Hz, 2H), 9.98 (s, 1H).…”

Desulfurization of Thiols for Nucleophilic Substitution

“…Due to the low bond energy of the RS-H bond, homolytic cleavage may occur under light irradiation to generate a RS • radical, which would be readily trapped by a trivalent phosphorus, resulting in the cleavage of the C–S bond to generate an alkyl radical for hydrogenation. ,, Based on these findings, it has been determined that hydroalkylation of alkenes with primary thiols can also be successfully achieved through a radical desulfurization process . Primary benzyl thiols can attack a hypervalent iodine, such as Dess–Martin periodinane (DMP), and the subsequent elimination affords esters, in which the ArCO 2 – and R 1 R 2 CH– moieties are derived from the DMP reagent and thiols, respectively . Primary and secondary benzyl thiols can be desulfurized and oxidized to aldehydes and ketones, respectively.…”