Pd (II)-promoted base hydrolysis of 2-cyano-1, 10-phenanthroline has been s
tudied. The reaction is first order each in metal-substrate complex and in
hydroxide ion. The second order rate constant for Pd (II)-catalysis process
is more than 10(5) that for alkaline hydrolysis in the absence of metal io
n. The mechanistic studies of this reaction are very interesting and give s
ome result in spite of the nickel ion catalysing mechanism. The entire acce
leration is accounted for by decreasing the DeltaH#. The mechanism of metal
-catalysed addition to the nitrile involves one step external attack rather
than the attack of nucleophile from the metal coordination sphere.