William D. McGhee

Isocyanates from primary amines and carbon dioxide: ‘dehydration’ of carbamate anions

Carbamate anions, derived from primary amines CO2 and an added base (e.g. NEt3), undergo rapid reaction with electrophilic ‘dehydrating agents’(e.g. POCl3, P4O10) to give the corresponding isocyanates in excellent yields.

Highly selective generation of urethanes from amines, carbon dioxide and alkyl chlorides

Generation of carbamate anions from either a primary or secondary amine, carbon dioxide and a stoichiometric amount of a pentaalkylguanidine followed by the addition of alkyl chlorides gives high yields of urethanes.

Conversion of amines to carbamoyl chlorides using carbon dioxide as a phosgene replacement

Abstract Dialkyl carbamates, generated from amines and carbon dioxide, are converted to their corresponding carbamoyl chlorides using thionyl chloride in the presence of added tertiary amine base.