One-step conversion of 2-amino-N'-arylbenzamidines into 3-aryl-4-imino-3,4-dihydroquinazoline-2-carbonitriles using 4,5-dichloro-1,2,3-dithiazolium chloride.
2-Amino-N'-arylbenzamidines react with 4,5-dichloro-1,2,3-dithiazolium chloride (Appel salt) in the presence of Hünig's base (2 equiv) to give in one step 3-aryl-4-imino-3,4-dihydroquinazoline-2-carbonitriles in 53-81% yields. Nine examples are presented along with the single-crystal X-ray structure of 4-imino-3-phenyl-3,4-dihydroquinazoline-2-carbonitrile. Furthermore, the behavior of the latter toward both acid and base hydrolysis is investigated. All new compounds are fully characterized, and a mechanistic rationale for the formation of the iminoquinazolines is provided.
Department of Chemistry, University of Cyprus , P.O. Box 20537, 1678 Nicosia, Cyprus.
Styliana I
SI
Mirallai
Manolis J
MJ
Manos
Panayiotis A
PA
Koutentis
D007097:Imines / Q000737:chemistry*; D015394:Molecular Structure; D009570:Nitriles / Q000138:chemical synthesis* / Q000737:chemistry; D011799:Quinazolines / Q000138:chemical synthesis* / Q000737:chemistry; D013844:Thiazoles / Q000737:chemistry*
C570987:4,5-dichloro-1,2,3-dithiazolium chloride; D007097:Imines; D009570:Nitriles; D011799:Quinazolines; D013844:Thiazoles