Mercaptoacetic Acid and Derivatives

Abstract

The article contains sections titled: 1. Introduction 2. Physical Properties 3. Chemical Properties 4. Production 5. Analysis 6. Transportation and Storage 7. Toxicology 8. Uses

Solution-Processed Cu2S Nanostructures for Solar Hydrogen Production

“…The peak at ∼930 cm –1 in Figure c is ascribed to C–COO – stretching, while no peak at ∼907 cm –1 corresponding to C–COOH stretching was observed . These results indicate that the amine group in EA deprotonated mainly the carboxylic acid group rather than the thiol group in TGA to form carboxylate anions, owing to the lower p K a value of the carboxylic acid group (p K a = 3.83) compared to the thiol group (p K a = 9.3) . A major difference was found in the low wavenumber range in Figure d, where a broad peak between 500 and 525 cm –1 appears only in the 0.35 M CuCl 2 molecular ink.…”

“…39 These results indicate that the amine group in EA deprotonated mainly the carboxylic acid group rather than the thiol group in TGA to form carboxylate anions, owing to the lower pK a value of the carboxylic acid group (pK a = 3.83) compared to the thiol group (pK a = 9.3). 40 A major difference was found in the low wavenumber range in Figure 4d, where a broad peak between 500 and 525 cm −1 appears only in the 0.35 M CuCl 2 molecular ink. This signal is characteristic of a −S−S− bond 41 and could be formed by the oxidation of the thiol group in TGA, 42 the reaction of which is displayed in Figure 4e.…”

Lewis Acid Promoted Deprotection of Benzylidene Acetals and p-Methoxybenzyl Ethers with Mercaptoacid Acid as Scavenger

“…Since benzylidene acetals and PMB-ethers are labile under acidic conditions, we opted for a carboxylic acid functionalized scavenger rather than an amine functionalized counterpart. Mercaptoacetic acid (thioglycolic acid, CAS: 68-11-1) is a cheap reagent used as a disulfide reductant in hair permanent (as ammonium thioglycolate) . Like ethanethiol (EtSH), which previously has been used to cleave benzylidene acetals , and PMB-ethers, it possesses a sulfur nucleophile and the desired carboxylic acid handle for deprotonation by, e.g., bicarbonate during the workup procedure.…”

“…Mercaptoacetic acid (thioglycolic acid, CAS: 68-11-1) is a cheap reagent used as a disulfide reductant in hair permanent (as ammonium thioglycolate). 26 Like ethanethiol (EtSH), which previously has been used to cleave benzylidene acetals 11,12 and PMB-ethers, 27 it possesses a sulfur nucleophile and the desired carboxylic acid handle for deprotonation by, e.g., bicarbonate during the workup procedure. First, our focus was on the benzylidene derivatives, as it was expected to be the more reactive of the two target protecting groups.…”