Biomimetic building-up of the carbamic moiety: the intermediacy of carboxyphosphate analogues in the synthesis of N-aryl carbamate esters from arylamines and …
The reaction of aromatic amines with dimethyl carbonate (DMC) or diphenyl carbonate (DPC) in the presence of organo-phosphorus acids [Ph2P (O) OH (1);(PhO) 2P (O) OH (2);(BuO) 2P (O) OH/(BuO) P (O)(OH) 2 equimolar mixture (3)] affords carbamate esters, ArNHC (O) OR (R= Me, Ph) with high selectivity. The catalytic role played by the P-acid has been investigated and rationalized in terms of a reaction mechanism involving the ...