Pyridinolysis of Phenyl N-Phenyl Phosphoramidochloridate in Acetonitrile

Abstract

Kinetics and mechanism of the aminolyses for various substrates have been studied extensively by this lab. The studied substrates are dominantly (R1O)(R2O)P(=O or S)Cl and R1R2P(=O or S)Cl-type where R1 and R2 are alkyl and/ or phenyl (aryl). Herein, the nucleophilic substitution reactions of phenyl N-phenyl phosphoramidochloridate (7), involving anilino (C6H5NH) ligand, with X-pyridines are investigated kinetically in acetonitrile (MeCN) at 35.0 ± 0.1 oC (Scheme 1). The aim of this work is to gain further information into the reactivity and mechanism depending on the variation of the two ligands as well as to compare with the pyridinolyses of chlorophosphates: dimethyl [1: (MeO)2P(=O)Cl], 1a diethyl [2: (EtO)2P(=O)Cl], 1a dipropyl [3: (PrO)2P(=O)Cl], 1b dibutyl [4: (BuO)2P(=O)Cl], 1c di-isopropyl [5: (i-PrO)2P(=O)Cl], 1d and Y-aryl phenyl [6: (PhO)(YC6H4O)P(=O)Cl] 1e chlorophosphates. The number-ing of the substrates of 1-6 follows the sequence of the summation of the Taft steric constants of the two ligands, R