Phosphorus oxychloride → 1,4-Dichloro-7-(3-cyanophenyl)isoquinoline

Participants

Reaction Steps

A solution of POCl3 (0.545 kg, 3.56 mol) in MeCN (0.76 L) was added to a suspension of 4-chloro-7-(3-cyanophenyl)isoquinolinone (0.50 kg, 1.78 mol) in boiling MeCN (4.25 L) under N2 over 1 hour. The mixture was heated at reflux overnight and then cooled to room temperature. The solid was collected by filtration, washed with MeCN (0.5 L) and dried in vacuo at 70° C. to give 1,4-dichloro-7-(3-cyanophenyl)isoquinoline (0.54 kg) as a creamy coloured solid which could be used without further drying or purification. The filtrate was slowly quenched with HCl (1N; 2.6 mL) which gave a second crop of 60 g of material which was filtered and washed with MeCN (0.5 L), which again could be used without further drying or purification.

Provenance & Evidence