Darstellung, Tautomerieverhalten und Wasserstoffbrücken‐bindung von 2‐Heteroarylamino‐thiazolen

Abstract

2‐Heteroarylamino‐thiazole lassen sich nach der Methode von HANTZSCH aus heteroaromatisch substituierten Thioharnstoffen darstellen. Die UV‐ und IR‐spektroskopische Untersuchung zeigt, daß diese Verbindungen in der Aminoform vorliegen. Sie sind im festen Zustand über NH…︁N‐Brücken assoziiert, wobei das Ringstickstoffatom des Thiazols als Protonenakzeptor fungiert.

Possibility of the Existence of Donor–Acceptor Interactions in Bis(azole)amines: An Electronic Structure Analysis

“…Compounds belonging to the bis(azole)amine class are known to form salts of multiple varieties, including dibasic salts . The partial atomic charges obtained from natural bond orbital analysis (NBO) indicated two possible sites for protonation in TT , TI , and TO systems.…”

“…Compounds belonging to the bis(azole)amine class are known to form salts of multiple varieties, including dibasic salts. 61 The partial atomic charges obtained from natural bond orbital analysis (NBO) indicated two possible sites for protonation in TT, TI, and TO systems. Our previous studies on thiazolylguanidines, 27 biguanides, 25 guanylthioureas, 24 and pyridylthiazolamines 28 23 reported the divalent N(I) character of the NHC coordinated nitrogen species (I).…”

“…Thiazolamine derivatives (TT, TI, and TO) are highly basic as they readily form salts of acetate, trifluoroacetate, 1,1,1trifluoromethanesulfonate, perchlorate, picrate, and hydrochloride. 61 In principle, protonation can occur either at the ring nitrogen or central nitrogen; hence, it is important to establish the preferred protonation center and to explore the electronic character of the resultant species. Quantum chemical calculations using DFT (density functional theory) method have been performed to explore the same.…”