主权项 |
1. A process for reacting reagents: (i) CS2, (ii) a haloform or reactive equivalent thereof, and (iii) a ketone or aldehyde of the structure R1C(═O)R2, and optionally (iv) a mercaptan of the structure R3SH, wherein R1, R2 and R3 are independently hydrogen or hydrocarbyl groups, provided that at least one of R1 and R2 is a hydrocarbyl group, and wherein R3 is a hydrocarbyl group, to provide a trithiocarbonate acid product of the general structure:
HO2C—CR1R2—S—C(═S)—S—Y where Y is —CR1R2—CO2H or R3 said process comprising:
(a) mixing, in a single vessel, reagents (i), (ii), (iii), and (iv) when present, where the resulting mixture is free of any base reagent, and then, after mixing reagents (i), (ii), (iii), and (iv) when present, adding to the vessel (v) a metal hydroxide base, in an organic solvent in which said ketone or aldehyde, said haloform, and said trithiocarbonate product are soluble; whereby the base-neutralized form of said trithiocarbonate product is formed from the reaction of the base (v) and the mixture of reagent (i) and the haloform (ii) and the ketone or aldehyde (iii) and the optional mercaptan (iv), and whereby an aqueous phase subsists along with an organic phase; (b) optionally removing the aqueous phase and any solids present at the end of step (a); (c) thereafter mixing with the mixture remaining in the vessel, an acid; whereby a trithiocarbonate acid is formed from the reaction of said trithiocarbonate and said acid, and whereby an aqueous phase subsists along with an organic phase; (d) optionally removing the aqueous phase and any solids present at the end of step (c); whereby an organic phase is provided in which said trithiocarbonate acid is dissolved; and (e) optionally isolating said trithiocarbonate acid from said organic phase of step (d). |