New access to thioglycolurils by condensation of 4,5-dihydroxyimidazolidin-2-ones(thiones) with HSCN
摘要:
A general and highly effective protocol for the direct synthesis of mono- and dithioglycolurils containing various substituents at the 1,3-nitrogen atoms has been developed based on the condensation of easily accessible dihydroxyimidazolidin-2-ones with HSCN under mild reactions conditions. (C) 2015 Elsevier Ltd. All rights reserved.
precursor of all cucurbiturils, its sulfur analog represents a yet unmet syntheticchallenge. The reaction between glyoxal and thiourea was found to stop at the level of dihydroxyimidazolidine-2-thione, which is quite unstable under various acidic conditions. In an attempt to answer these questions, several stable analogs of thioglycoluril, that is, monothioglycoluril, ditolylthioglycoluril, and its diether