Synthetic utility of Kabachnik–Fields reaction: a convenient one-pot three-component synthesis of N-phenyl isoquinolone-1-phosphonates

A convenient, one-pot three-component synthesis of novel N-phenyl isoquinolone-1-phosphonates (4a–4g) using the Kabachnik–Fields reaction, starting from ethyl 2-(2-formyl-4,5-dimethoxyphenyl) acetate (1) and anilines (2a–2g) is described. The aldehyde (1) on reaction with substituted anilines (2a–2g) and triethyl phosphite in acetonitrile using trifluroacetic acid as catalyst provides N-phenyl isoquinolone-1-phosphonates (4a–4g) in good yields.