Alkyl carbamate prepn. - from amine(s) by catalytic reaction

摘要

Alkyl carbamates of formula (I), in which R1 is an alkyl gp., R2 and R3 are H, alkyl or together form a ring opt. contg. hetero-atoms, are made by reacting an amine of formula (II) with a cpd. of formula R1X, in which X is a nucleofugic gp., in apolar solvent e.g. benzene, heptane, etc. with a finely-divided alkali or alkaline earth carbonate or bicarbonate, in presence of a quat. ammonium or phosphonium salt and a crown ester or cryptane as catalyst.