Formanilide and carbanilide from aniline and carbon dioxide

Abstract Earlier syntheses of formamides from the catalytic hydrogenation of CO 2 in the presence of amines were only successful for the preparation of dialkylformamides. After an analysis of the reason for the failure of the reaction using aniline as a starting material, formanilide has been prepared, for the first time, from CO 2 , H 2 and aniline with the use of 1,8-diazabicyclo[5.4.0]undec-7-ene. Omission of the H 2 reductant causes the selectivity to switch to the production of carbanilide (1,3-diphenylurea).