Dalton Trans 2021 Apr;50(15):5351-5359
Dipartimento di Chimica e Chimica Industriale, University of Pisa, Via G. Moruzzi 13, I-56124 Pisa, Italy. and CIRCC, via Celso Ulpiani 27, I-70126 Bari, Italy.
The catalytic potential of a large series of easily available metal carbamates (based on thirteen different non-precious metal elements) was explored for the first time in the coupling reaction between 2-aryl-aziridines and carbon dioxide, working under solventless and ambient conditions and using tetraalkylammonium halides as co-catalysts. The straightforward synthesis of novel [NbCl3(O2CNEt2)2], NbCl, and [NbBr3(O2CNEt2)2], NbBr, is reported. The niobium complex NbCl, in combination with NBu4I, emerged as the best catalyst of the overall series to convert aziridines with small N-alkyl substituents into the corresponding 5-aryl-oxazolidin-2-ones. Read More