Robuta

https://www.sigmaaldrich.com/PL/en/technical-documents/technical-article/chemistry-and-synthesis/metathesis/n-heterocyclic-carbenes
NHC (N-heterocyclic carbenes) are ligands for rapid synthesis of novel organometallic complexes. NHC ligands have practical use when bound to metals.
nheterocyclic
https://www.vedantu.com/question-answer/are-the-different-types-of-carbenes-a-singlet-class-11-chemistry-cbse-5fe2d486a76f17528ce7c2b7
What are the different types of carbenes A Singlet B Triplet C Both of the above D None of the above
different typescarbenessingletclass
https://www.sigmaaldrich.com/JP/en/technical-documents/technical-article/chemistry-and-synthesis/metathesis/n-heterocyclic-carbenes
NHC (N-heterocyclic carbenes) are ligands for rapid synthesis of novel organometallic complexes. NHC ligands have practical use when bound to metals.
nheterocyclic
https://www.sintef.no/en/publications/publication/1354945/
bio basedhomogeneousmaskedheterocycliccarbenes