4-Arylaminoquinazoline-2-carbonitriles 5a - i were obtained by a one-step synthesis in moderate to good yield by reacting 2-aminoarylbenzimidamides 3a - i with tetracyanoethylene (TCNE, 4) in ethyl acetate at r. t. for 4 - 6 h. The structure of the selected benzimidamide 3c was determined by single crystal X-ray diffraction.
A short and facile synthesis of a series of 4-[( Z)-4-(arylimino)-3,4-dihydroquinazolin-2(1 H)-ylidene]cyclohexa-2,5-dien-1-ylidene}malononitrile was accomplished in moderate to good yields via Charge-transfer complexes between 2-amino-N′-aryl-benzimidamide derivatives and 7,7,8,8-tetracyanoquinodimethane. The structure of the products were established on the basis of their elemental analysis, IR, NMR (1H and 13C) and mass spectrometry data.
A series of 2-arylazobenzonitriles (5a - f) have been obtained through a novel indazolimine-arylazobenzonitrile rearrangement. The products 5a - f were fully characterized and their structure elucidated on the basis of spectroscopic and analytical data. The mechanism of formation of 5a - f is discussed.