Synthesis Of β-Hydroxy Sulfides Research Articles

Tuning Selectivity in the Visible-Light-Promoted Coupling of Thiols with Alkenes by EDA vs TOCO Complex Formation.

The visible-light-promoted catalyst-free condition has been demonstrated for self- and cross-coupling reactions of thiols in an ambient atmosphere. Further, synthesis of β-hydroxysulfides is accomplished under very mild conditions involving the formation of an electron donor-acceptor (EDA) complex between a disulfide and an alkene. However, the direct reaction of thiol with alkene via the formation of a thiol-oxygen co-oxidation (TOCO) complex failed to produce the desired compounds in high yields. The protocol was successful with several aryl and alkyl thiols for the formation of disulfides. However, the formation of β-hydroxysulfides required an aromatic unit on the disulfide fragment, which supports the formation of the EDA complex during the course of the reaction. The approaches presented in this paper for the coupling reaction of thiols and the synthesis of β-hydroxysulfides are unique and do not require toxic organic or metal catalysts.

Synthesis of β-hydroxysulfides via visible-light-driven and EDA complex-promoted hydroxysulfenylation of styrenes with heterocyclic thiols in EtOH under photocatalyst-free conditions

A convenient, environmentally friendly, visible-light-driven and EDA complex-promoted direct hydroxysulfenylation of styrenes under photocatalyst- and transition metal-free has been developed with O2 as the oxygen source and EtOH as the solvent.

Intermolecular difunctionalization of alkenes: synthesis of β-hydroxy sulfides.

Direct difunctionalization of carbon–carbon double bonds is one of the most powerful tools available for concomitant introduction of two functional groups into olefinic substrates. In this context, vicinal hydroxysulfenylation of unactivated alkenes has emerged as a novel and straightforward strategy for the fabrication of β-hydroxy sulfides, which are extremely valuable starting materials in constructing various natural products, pharmaceuticals, and fine chemicals. The aim of this review is to summarize the most representative and important reports on the preparation of β-hydroxy sulfides through intermolecular hydroxysulfenylation of the corresponding alkenes with special emphasis on the mechanistic features of the reactions.

Aerial dioxygen activation vs. thiol-ene click reaction within a system.

Markovnikov or anti-Markovnikov selective thiol-ene click (TEC) reactions and the synthesis of β-hydroxysulfides via aerial dioxygen activation are prevalent C-S bond forming reactions of styrenes and thiophenols. Herein, by choosing appropriate environments using solvents with additives or neat conditions, any one of these three reactions was achieved exclusively in excellent yields.

ChemInform Abstract: Efficient Synthesis of β‐Hydroxy Sulfides by Microwave‐Promoted Ring Opening in (+)‐3‐Carene trans‐Epoxide with Sodium Thiolates.

Reaction of (+)-3-carene trans-epoxide with sodium thiolates in methanolic solution in a microwave oven at 140 °C for 35–40 min affords corresponding (1S,3S,4S,6R)-4-sulfanylcaran-3-ols in 75–95% yields.

Efficient synthesis of β-hydroxy sulfides by microwave-promoted ring opening in (+)-3-carene trans-epoxide with sodium thiolates

Reaction of (+)-3-carene trans-epoxide with sodium thiolates in methanolic solution in a microwave oven at 140 °C for 35–40 min affords corresponding (1S,3S,4S,6R)-4-sulfanylcaran-3-ols in 75–95% yields.

Magnesium Chloride–Catalyzed Thiolysis of Epoxides: Synthesis of β-hydroxy Sulfides

A mild and convenient ring opening of epoxides with thiophenol and its derivatives takes place at room temperature in the presence of magnesium chloride as catalyst to afford the corresponding β-hydroxy sulfides along with minor amounts of 2-chlorocycloalkanols in good yields. When the crude reaction mixtures are treated with aqueous sodium hydroxide solution, pure 2-arlythiocycloalkanols are obtained in good yields.

LiOH-Catalyzed Simple Ring Opening of Epoxides Under Solvent-Free Conditions

LiOH has been found to be a very simple and selective catalyst for the rapid and mild synthesis of β-hydroxy sulfides and β-hydroxyl nitriles by ring opening of epoxides with aromatic, aliphatic, and heterocyclic thiols and trimethylsilyl cyanide at room temperature under solvent free conditions. All the reactions proceeded satisfactorily in short times and afforded the corresponding products in good to excellent yields with high regioselectivity and chemoselectivity under mild reaction conditions.

Efficient Synthesis of β-Hydroxy Sulfides and β-Hydroxy Sulfoxides Catalyzed by Cu/MgO Under Solvent-Free Conditions

Regio-, stereo-, and chemoselective ring opening of epoxides with thiols using Cu/MgO as a heterogeneous catalyst has efficiently been carried out to produce the corresponding β-hydroxy sulfides in excellent yields at room temperature under solvent-free conditions. The treatment of the epoxides with thiols and 50% aqueous H2O2 in the presence of the same catalyst at room temperature affords the β-hydroxy sulfoxides in excellent yields.

Regioselective Reaction of Epoxides with Disulfides Using Zn/AlCl3 System: A Simple Synthesis of β-Hydroxy Sulfides

Epoxides are regioselectively cleaved by zinc thiolate intermediate, generated from disulfides in the presence of Zn/AlCl3 system, to afford high yields of the corresponding β-hydroxy sulfides.