Patent ID: 7977487

Claim:
A process for preparing a N,N-bis(pyridin-2-ylmethyl)-1,1-bis(pyridin-2-yl)-1-aminoalkane compound of formula 1, or a transition metal complex salt thereof as ligand, where R 1 is C 1 -C 6 alkyl, phenyl or benzyl, said process comprising: 1) reacting dipyridyl ketone with hydroxylamine and reducing the resulting oxime, without isolating it, to provide an amine of formula 2 2) alkylating the amine of formula 2 first with 1 to 1.5 mole equivalents of picolyl chloride and then with a further 1 to 1.5 mole equivalents of picolyl chloride, to provide an amine of formula 3 3) converting the amine of formula 3 into a fluoroborate salt by addition of HBF 4 , and then liberating the amine of formula 3 from the fluoroborate salt by addition of a base, and 4) alkylating the amine of formula 3 with an alkyl halide of the formula R 1 -hal to provide the compound of formula (1), and, optionally, 5) converting the compound of formula (1) into the transition metal complex salt, by further reacting the compound of formula (1) with a transition metal salt.