| abstract |
Process for preparing N,N,N,''N''-tetraacetyl compounds of the general formula WHEREIN Ac represents acetyl -OCCH3, R represents a straight, or branch chained alkylene group with 1 - 12 C-atoms, or equals zero; OR R represents a substituted or unsubstituted phenylene, benzylidene, cyclohexylidene, naphthylene, diphenylene methane or dicyclohexylidene methane group, the preparation being performed by the N-acetylation of N,N''-diacetyl compounds of the general formula WHEREIN Ac and R have the meaning indicated above, with ketene in the presence of a catalyst and a solvent, the invention consisting of the use of a catalyst of the group consisting of an inorganic fluorine compound of the element boron, silicon, nitrogen, phosphorus, arsenic, antimony, bismuth, titanium, and vanadium, singly or in a mixture. |