Ring closure reactions with nitriles. II. Formation of pyrrolo[1,2‐a] quinazolines and thiazolo[3,2‐a] quinazolines

Abstract 2‐Quinazolinepropionic acids have been obtained from the reactions of potassium cyanide with o‐carboxy‐ or o‐acyl‐3‐chloropropionanilides. Some of these compounds have been cyclized to pyrrolo [1,2‐a] quinazolines. The reaction of an o‐carbethoxy‐2‐chloroacetanilide with potassium thiocyanate formed a 2‐quinazolinylthioacetic acid, which was cyclized to a thiazolo‐[3,2‐a]quinazoline. A mechanism is presented for the formation of these compounds.