Reaktion von methylenaktiven Nitrilen und Cyanamid mit acylierten Enaminen

✍ Scribed by Dr. K. Gewald; Dr. H. Schäfer; Dr. P. Bellmann

• Publisher: John Wiley and Sons
• Year: 1982
• Tongue: English
• Weight: 503 KB
• Volume: 324
• Category: Article
• ISSN: 1615-4150
• DOI: 10.1002/prac.19823240611

✦ Synopsis

Reaction of Methylene Active Nitriles and Cyanamide with Acylated Enamines

The addition products from enamines onto isocyanates and isothiocyanates, i.e. substituted β‐aminoacrylo amides 1 and thioamides 2, react with malononitrile to yield the 6‐amino‐1‐aryl‐5‐cyano‐pyridin‐2‐ones 3 and ‐thiones 4 among them 5,6,7,8‐tetrahydroisoquinolin‐1‐ones and ‐thiones. From ethyl cyanoacetate the 5‐cyano‐6‐hydroxy‐pyridin‐2‐ones 7 and from benzoyl acetonitrile the 6‐phenyl‐pyridin‐2‐ones 8 are formed. The replacement of malononitrile by cyanamide yields the 2‐amino‐3‐aryl‐pyrimidin‐4‐ones 5 and ‐thiones 6 among them 5,6,7,8‐tetrahydroquinazolin‐4‐ones and ‐thiones. The not isolated β‐acyl enamines derived from enamines and acid chlorides react with malononitrile or cyanamide to form the pyridin‐2‐ones 14 or pyrimidin‐2‐ones 15 caused by Dimroth‐rearrangement.