Reactions of acyl phosphates. Base hydrolysis of [Co(NH3)5OPO3COCH3]+ and the metal hydroxide promoted hydrolysis of acetyl phenyl phosphate

Tracer 18O studies have established that base hydrolysis of coordinated acetyl phosphate in [(NH3)5Co-OPO3COCH3]+ (kOH 0.53 mol-1 dm3 s-1, 25°C, I 1.0 NaClO4) proceeds with exclusive carbon-oxygen bond fission. The hydrolysis of acetyl phenyl phosphate monoanion is significantly catalysed by the exchange-inert hydroxo complex [(NH3)5Co-OH]2+ (kMOH 2.9 × 10-2 mol-1 dm3 s-1, 25°) which operates through a nucleophilic pathway involving attack at carbonyl carbon.