Direct Synthesis of Isothiocyanates from Isonitriles by Molybdenum-Catalyzed Sulfur Transfer with Elemental Sulfur†
journal contributionposted on 04.09.2002, 00:00 by Waldemar Adam, Rainer M. Bargon, Sara G. Bosio, Wolfdieter A. Schenk, Dietmar Stalke
The direct molybdenum-catalyzed sulfuration of a variety of isonitriles with elemental sulfur or propene sulfide as sulfur donors affords the corresponding isothiocyanates in good yields and under mild reaction conditions. A catalytic cycle is suggested, in which the molybdenum oxo disulfur complex operates as the active sulfur-transferring species. A novel adduct between the isonitrile and the molybdenum complex has been characterized by X-ray analysis and its association constant determined by UV−vis spectroscopy, but this adduct appears not to be involved in the sulfur-transfer process.