Indium-Catalyzed Reductive Dithioacetalization of Carboxylic Acids with Dithiols: Scope, Limitations, and Application to Oxidative Desulfurization

Abstract

In this study an InI-TMDS (1,1,3,3-tetramethyldisiloxane) reducing system effectively catalyzed the reductive dithioacetalization of a variety of aromatic and aliphatic carboxylic acids with 1,2-ethanedithiol or 1,3-propanedithiol leading to the one-pot preparation of either 1,3-dithiolane derivatives or a 1,3-dithiane derivative. Also, the intact indium catalyst continuously catalyzed the subsequent oxidative desulfurization of an in situ formed 1,3-dithiolane derivative, which led to the preparation of the corresponding aldehydes.

Visible‐Light Photoredox‐Catalyzed Thioacetalization of Aldehydes Under Metal‐Free and Solvent‐Free Conditions

“…2‐( o ‐Tolyl)‐1,3‐dithiolane (5 a) : Following the general procedure, using o ‐tolualdehyde (0.120 g, 1.0 mmol), 1,2‐ethanedithiol (0.103 g, 1.1 mmol), eosin Y (0.6 mg, 0.1 mol%), then purified by column chromatography (SiO 2 , 10% ethyl acetate in hexanes) to provide 5 a as the yellow oil ( 0.159 g, 81% yield). 1 H NMR (400 MHz, CDCl 3 ): δ 7.79 (d, J =8.0 Hz, 1H), 7.26–7.12 (m, 3H), 5.88 (s, 1H), 3.54–3.32 (m, 4H), 2.43 (s, 3H).…”

PhIO-Mediated oxidative dethioacetalization/dethioketalization under water-free conditions

“…. 41 Following the general procedure, 1d was purified by silica gel chromatography (EtOAc/PE = 2/98). Yield: 2.14 g, 95%, a white solid, mp.…”

“…1 H NMR (400 MHz, CDCl3) δ 7.85 (dd, J 7.9, 1.7 Hz, 1H), 7.53 (dd, J 8.0, 1.3 Hz, 1H), 7.31 (td, J 7.6, 1.3 Hz, 1H), 7.11 (td, J 7.6, 1.7 Hz, 1H), 6.05 (s, 1H), 3.50 -3.42 (m, 2H), 3.42 -3.33 (m, 2H). 13 41 Following the general procedure, 1m was purified by silica gel chromatography (EtOAc/PE = 0/100). Yield: 1.7 g, 99%, colorless oil, mp.…”

Dihydrosulfenylation of Alkynes with Thiols Using a Nickel Catalyst through a Radical Process

“…The preparation of dithioacetals has been developed by numerous researchers, which are usually synthesized by reacting carbonyl compounds with thiols. [1,2] The obtained compounds are widely used as convenient synthetic intermediates. [2,3] On the other hand, a convenient synthesis of dithioacetals from alkynes is quite limited.…”

“…[1,2] The obtained compounds are widely used as convenient synthetic intermediates. [2,3] On the other hand, a convenient synthesis of dithioacetals from alkynes is quite limited. [5,6,7] As a general rule, the reaction of alkynes with thiols usually affords the corresponding vinyl sulfides in excellent yields.…”