58379-67-2Relevant articles and documents
Mechanism of thio acid/azide amidation
Kolakowski, Robert V.,Shangguan, Ning,Sauers, Ronald R.,Williams, Lawrence J.
, p. 5695 - 5702 (2007/10/03)
A combined experimental and computational mechanistic study of amide formation from thio acids and azides is described. The data support two distinct mechanistic pathways dependent on the electronic character of the azide component. Relatively electron-rich azides undergo bimolecular coupling with thiocarboxylates via an anion-accelerated [3+2] cycloaddition to give a thiatriazoline. Highly electron-poor azides couple via bimolecular union of the terminal nitrogen of the azide with sulfur of the thiocarboxylate to give a linear adduct. Cyclization of this intermediate gives a thiatriazoline. Decomposition to amide is found to proceed via retro-[3+2] cycloaddition of the neutral thiatriazoline intermediates. Computational analysis (DFT, 6-31+G(d)) identified pathways by which both classes of azide undergo [3+2] cycloaddition with thio acid to give thiatriazoline intermediates, although these paths are higher in energy than the thiocarboxylate amidations. These studies also establish that the reaction profile of electron-poor azides is attributable to a prior capture mechanism followed by intramolecular acylation.
Benzamidomethylation with (benzamidomethyl)triethylammonium chloride. 2. A simple method for benzamidomethylation of thiols, amines and carboxylic acids
Popovski, Emil,Klisarova, Ljiljana,Vikic-Topic, Drazen
, p. 927 - 936 (2007/10/03)
Thiols and amines were benzamidomethylated in water solution at room temperature with (benzamidomethyl)triethylammonium chloride (1) in the presence of a small quantity of triethylamine (pH>9). Benzamidomethyl thioethers (3a-d) and (benzamidomethyl)amines or di(benzamidomethyl)amines (5) were obtained in high yields (>90%) as well as S(CH2NHBz)2 in a reaction of 1 with Na2S. Benzamidomethyl esters RCOOCH 2NHBz were obtained (60-75%) in reactions of carboxylic acids with 1 in chloroform or dioxane.
Relative Ease of Transient Acyl Imine Formation via Selenoxide, Sulfoxide, and Sulfone β N-H Elimination. A Feasibility Study on the Preparation of Novel Peptide Analogues
Branchaud, Bruce P.,Tsai, Pei
, p. 5475 - 5478 (2007/10/02)
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