Proton inventory of phosphate monoanion catalyzed hydrolysis of S-ethyl trifluorothioacetate

Kinetics and Mechanisms of Reactions of Thiol, Thiono, and Dithio Analogues of Carboxylic Esters with Nucleophiles

“…2i A proton inventory was carried out for this reaction in the presence of dihydrogen phosphate monoanion at pH 4.2. 10 The proton inventory plot 11 for the water reaction indicates the presence of three protons undergoing bonding changes in the transition state, in accordance with a previous finding. 2k For the phosphate monoanion reaction, only a one-proton transition state was found, as indicated by the linear proton inventory plot obtained.…”

“…The proton inventory plot 11 for the water reaction indicates the presence of three protons undergoing bonding changes in the transition state, in accordance with a previous finding 2k. For the phosphate monoanion reaction, only a one-proton transition state was found, as indicated by the linear proton inventory plot obtained . The latter result is in agreement with that of the imidazole-catalyzed hydrolysis of acetylimidazole and ethyl trifluorothiolacetate 2l…”

“…2k For the phosphate monoanion reaction, only a one-proton transition state was found, as indicated by the linear proton inventory plot obtained. 10 The latter result is in agreement with that of the imidazole-catalyzed hydrolysis of acetylimidazole and ethyl trifluorothiolacetate. 2l It has been found that molybdate dianion (MoO 4 2-) is a remarkable nucleophile toward 4-nitrophenyl thiolacetate.…”

“…The general base-catalyzed hydrolysis mechanism of ethyl trifluorothiolacetate is well established 2i. A proton inventory was carried out for this reaction in the presence of dihydrogen phosphate monoanion at pH 4.2 . The proton inventory plot 11 for the water reaction indicates the presence of three protons undergoing bonding changes in the transition state, in accordance with a previous finding 2k.…”

“…45 Bro ¨nsted β lg values for the acid-catalyzed decomposition of these substrates are small, in accordance with concerted general acid catalysis. 45 In the reactions of S-ethoxycarbonyl O-ethyl dithiocarbonate (9) with O-alkyl dithiocarbonate (ROCS 2 -) and O-alkyl thiocarbonate (ROCOS -) anions in 95% ethanol-water, the symmetrical pyrothiocarbonates, bis(ethoxythiocarbonyl) sulfide (10) and bis(ethoxycarbonyl) sulfide (11), are produced, respectively. The reaction of 9 with BuOCS 2yielded first BuOCS 2 -CSOEt and then BuOCS 2 CO 2 Et and (BuOCS) 2 S.…”