@article {43803,
	title = {Method for the analysis of free carbenes present after NHC-organocatalyzed transformations},
	journal = {European Journal of Organic Chemistry},
	year = {2017},
	month = {AUG},
	pages = {4500-4506},
	type = {Article},
	abstract = {In N-heterocyclic carbene (NHC) based organocatalysis, usually, the free carbene is generated in situ by treatment of the azolium salt with a base. Described herein is a method for the analysis of the NHC present in the reaction flask after the NHC-organocatalyzed reaction. For this, the reaction mixture was treated with elemental sulfur after the reaction and the thus-formed thiourea/thione derivative was isolated. Common NHC-catalyzed transformations such as benzoin reactions, Stetter reactions, homoenolate annulation reactions, and reactions proceeding via the ,-unsaturated acylazolium intermediate have been studied. The results indicate that after the reactions, 28-84\% of the initial carbenes exist in the free form.},
	doi = {10.1002/ejoc.201700903},
	author = {Das, Tamal Kanti and Biju, Akkattu T.}
}
