Synthesis of Imidazol-2-ylidenes by Reduction of Imidazole-2(3H)-thiones
01 Jan 1993-Synthesis (© Georg Thieme Verlag, Rüdigerstr. 14, 70469 Stuttgart, Germany. All rights reserved. This journal, including all individual contributions and illustrations published therein, is legally protected by copyright for the duration of the copyright period. Any use, exploitation or commercialization outside the narrow limits set by copyright legislation, without the publisher's consent, is illegal and liable to criminal prosecution. This applies in particular to photostat reproduction, copying, cyclostyling, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage.)-Vol. 1993, Iss: 06, pp 561-562
TL;DR: In this article, an improved synthesis of the title compounds was reported, and the N,N'-dialkylthioureas 1 with 3-hydroxy-2-butanone gave the imidazole-2(3H)-thiones 2 which on treatment with potassium in boiling tetrahydrofuran give the IMidazol-2ylidenes 3 in excellent yields
Abstract: An improved synthesis of the title compounds is reported. Reaction of the N,N'-dialkylthioureas 1 with 3-hydroxy-2-butanone gives the imidazole-2(3H)-thiones 2 which on treatment with potassium in boiling tetrahydrofuran give the imidazol-2-ylidenes 3 in excellent yields
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TL;DR: New methods for the synthesis of complexes with N-heterocyclic carbene ligands such as the oxidative addition or the metal atom template controlled cyclized isocyanides have been developed recently.
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