Eine neue Amidinsynthese mit Hilfe der Grignard‐Reaktion. 7. Mitteilung über Grignard‐Reaktionen [1]

Synthesis oftrans-N-2-aryl(heteryl)ethenamidines

“…trans-N-(fl-styryl)amidines or 2-arylethenamidines 2_ from 2-aryl-2-aminoethylamides 1 under Bischler-Napieralski conditions, along with structure proof and a speculative mechanism (Advani et al 1968). Subsequently a number of syntheses of such azabutadienes have appeared in the literature: Ring opening of 5-substituted-4-chloro-2-phenylpyrimidines by potassium amide in liquid ammonia (Va Meeteren and Van der Plas 1971); Grignard reactions or action of organolithium compounds on benzonitriles (Marxer 1972;Cook and Wakefield 1980;Compagnon et al 1982;Cook et al 1983); Dimerisation of nitdles having alpha hydrogen in the presence of hydrogen chloride + Contribution No. 752 from Research Centre * For correspondence 383 (Yanagida et al 1973;Yanagida 1975); Base treatment of N-(trans-styrylsulphonyl) amidines (Matier and Comer 1974, 1975, 1977; from N-vinyl-substituted chloroformamidines (Ried and Erie 1979); Acid decomposition of 5-amino-l-vinyl-4,5-dihydro-1 H-1,2, 3-triazole (lto et al 1983); Reaction of 2-aryl-4-arylidene-2-oxazolin-5-ones with nucleophiles (Islam et a11983) and reaction of electron-rich aromatics like indoles with 3-dimethylamino-2-(dimethylaminomethyleneamino) acrylic esters (Biere 1983).…”