Metal(II)-promoted hydrolysis of pyridine-2-carbonitrile to pyridine-2-carboxylic acid. The structure of [Cu(pyridine-2-carboxylate)2]center dot 2H(2)O

Pyridine-2-carbonitrile (2-CNpy) undergoes Cu(II) or Co(II)-promoted hydrol ysis to pyridine-2-carboxamide (piaH) and/or pyridine-2-carboxylic acid (py cH). the pathway of pycH formation depends on the presence of 2-amino-2-hyd roxymethyl-1,3-propanediol (AL(1)) and on the central atom. In the absence of AL(1) Co(II) or Cu(II) ions mediate piaH formation under mild reaction c onditions in the first hydrolytic step. Cu(II) ions assist in piaH transfor mation to pycH by subsequent reflux. In the presence of AL(1) and Co(II), a Co(II) complex containing pyoxaL(1) (2-(2-pyridinyl)-4,4-bis(hydroxymethyl )-2-oxazoline) is formed in the first stage, subsequent decomposition of py oxaL(1) under the reflux yields pycH. Under similar conditions, no solid Cu (II) complex with pyoxaL(1) can be isolated, but a Cu(Il) complex with coor dinated pyc(-) anions precipitates from the reaction mixture. The synthesis , spectral and magnetic properties of the complexes [Co(H2O)(2) (piaH)(2)]C l-2,[CO(H2O)(2)(pyc)(2)]. 2H(2)O, [Cu(H2O)(2)(piaH)(2)]Cl2, [Cu(pyc)(2)] an d [Cu(pyc)(2)]. 2H(2)O, including the structure determination of the latter one, are described. (C) 1998 Elsevier Science Ltd. All rights reserved.