Novel synthesis of aminoacetonitriles via the selective demethylation of quaternary ammonium salts

Making and Breaking of C-N Bonds: Applications in the Synthesis of Unsymmetric Tertiary Amines and α-Amino Carbonyl Derivatives

An operationally simple process has been developed for the synthesis of unsymmetrical amines and α-amino carbonyl derivatives in the absence of a catalyst, ligand, oxidant, or any additives. Contrary to known reductive amination methods, this protocol is amenable to substrates containing other reducible groups. This process effectively results in consecutive cleavage and formation of C-N bonds. DFT studies and Hammett analysis provide useful insight into the mechanism. The role of noncovalent interactions as a stabilizing factor have been examined in the protocol. A wide range of alkyl-bromides have been coupled efficiently with a variety of dimethyl anilines to get unsymmetric tertiary amines with yields up to 90%. This methodology was further extended to the synthesis of α-amino carbonyl derivatives with yields up to 93%.

Study on Extraction Separation of Thioarsenite Acid in Alkaline Solution by CO 3 2 - -Type Tri-n-Octylmethyl-Ammonium Chloride

To overcome the problem of arsenic separation and enrichment from an alkaline leaching solution in arsenic-containing dust, a CO 3 2 - -type tri-n-octylmethyl-ammonium chloride (TOMAC) method for extracting thioarsenite is proposed in this paper. Considering an alkaline leaching solution as the research object, after vulcanization pretreatment, TOMAC transformation and organic phase saturated extraction capacity were measured, and the extraction mechanism was preliminarily studied. First, Cl^--type quaternary ammonium salt was effectively transformed to HCO 3 - -type by treating organic phase with saturated NaHCO_3five times. TOMAC was effectively transformed from HCO 3 - to CO 3 2 - type by alkaline washing with 1.0 mol/l NaOH solution; this washing was repeated thrice. Thereafter, the effects of organic phase composition, phase ratio, extraction time, and temperature on the extraction and separation of arsenic were investigated. The results show that under the conditions of 30% CO 3 2 - -type TOMAC + 15% sec-octanol + 55% sulfonated kerosene, V_O/V_A = 1/1, and 5 min extraction at room temperature, the single-stage extraction rate of As^III is 85.2%. The As^III concentration in raffinate can be reduced to less than 1.33 × 10^-3 mol/l by four-stage countercurrent extraction, and the extraction rate of As^III can exceed 98.4%.