Cooperative catalysis with binary Lewis acid–Lewis base system for the coupling of carbon disulfide and epoxides

Abstract

The cycloaddition of epoxides with carbon disulfide proceeds effectively by using a binary catalyst system of tetradentate Schiff‐base aluminum complexes (designated as salenAlX) as Lewis acid in connection with a nucleophilic co‐catalyst, such as quaternary ammonium salt. The steric factor of the substituent groups on the aromatic rings of salenAlX and the anion of quaternary ammonium salt all have significant effects on the activity of the binary catalyst system, as well as the selectivities of the resultant cyclic products. The effects of temperature, time and the molar ratio of reactants were also investigated in detail with regard to propylene oxide with carbon disulfide, and a plausible mechanism was proposed. Copyright © 2012 John Wiley & Sons, Ltd.

Single-Site Bifunctional Catalysts for COX (X = O or S)/Epoxides Copolymerization: Combining High Activity, Selectivity, and Durability

“…These results showed that the Co­(III)-based catalyst is unsuitable for the COS/PO copolymerization. Prior to the present study, we utilized a binary system composed of salen-type cobaltate complex and a ionic ammonium salt for mediating the coupling reaction of carbon disulfide and epoxides, but unfortunately, no product was found …”

Convenient synthesis of 1,3-dithiolane-2-thiones: cyclic trithiocarbonates as conformational locks

“…1 The procedures described previously for such a transformation used carbon disulfide in presence of a base and/or catalyst, and included an in situ formation of a xanthogenate or a similar intermediate, and then its reaction with an epoxide 2,[5][6][7][8][10][11][12][13][14] (for a detailed critical consideration of the literature data see ref.…”

“…We did not isolate these compounds, but the formation of some 1,3-oxathiolane-2-thiones in certain conditions was observed previously. 2,5,6,14 It is also known that these compounds react with excess carbon disulfide to give trithiocarbonates. 2,6 Apparently, in our case the subsequent addition of a nucleophile (Nuc = EtOCS 2 -, EtO -, or MeO -from the solvent) to probable intermediates 7 occurred quickly and caused cleavage of the heterocycle.…”

“…2,3 They are used as building blocks in the synthesis of new antibiotics, and as versatile ligands and polymers. [2][3][4][5][6] Trithiocarbonates are also of commercial importance in a wide variety of applications, for example as rubber stabilizers, ore flotation agents, and additives for lubricants and fuels. [7][8][9] Besides, they exhibit a remarkably high liver disorder suppressing effect, and hypocholesteremic, hypotriglyceridemic, radioprotective, and insecticidal activity.…”

“…[9][10][11][12] One of the most efficient methods for the synthesis of cyclic trithiocarbonates reported in literature is based on the reaction of epoxides with carbon disulfide (CS 2 ) in presence of a base and/or a catalyst. 2,[5][6][7][8][10][11][12][13][14] However, these procedures often suffer from low yields and poor selectivity. Depending on the catalyst and reaction conditions, a variety of products can be Our modified procedure has the same stereochemical outcome.…”