Patent ID: 8134014

Claim:
Process for the dimerization of isocyanates comprising reacting: a) at least one organic isocyanate, b) a catalyst containing at least one pyridine derivative corresponding to the formula (II) where R 1 , R 6 are, independently of one another, identical or different, substituted or unsubstituted and/or branched hydrocarbon radicals, R 2 , R 4 are, independently of one another, hydrogen or identical or different hydrocarbon radicals which may be substituted by heteroatoms or functional groups and/or be branched and R 3 , R 5 are, independently of one another, radicals having the definition of the radicals R 2 , R 4 or together form a cyclic, 4- to 7-membered hydrocarbon segment which bridges the two N atoms and may be substituted by hydrocarbon radicals, heteroatoms or functional groups and/or be unsaturated c) optionally solvents and d) optionally additives are reacted.