2-Hydropolyfluoroalk-2-anoates, reaction with 2-aminopyridines

Reaction of 2 equiv of 2-aminopyridines with 2-hydropolyfluoroalk-2-anoates 351 in MeCN in the presence of NEts at 90 °C for 50 h afforded a mixture of the isomeric 2-oxo-2H- and 4-oxo-4//-pyrido[l,2-n]pyrimidines 110 and 111. Reaction of 3 equiv of 2-amino-pyridines and 2-hydropoly-fluoroalk-2-enoates 351 in MeCN in the presence K2CO3 could be accelerated by ultrasonic irradiation (125W). 2-Amino-6-methylpyridine yielded only 2-substituted 6-methyl-4//-pyrido[l,2-n]pyrimidin-4-ones 111 (R = 6-Me), whereas 2-amino-5-bromopyridine gave a mixture of 7-bromo-4//-pyrido[l,2-n]pyrimidin-4-one (111, R = 7-Br, R = CF2C1) and 2-(chlor-o,difluoromethyl)-6-bromoimidazo[l, 2-n]pyrimidine-3-carboxylate in 44 and 8% yields, respectively (97JCS(P 1)981). Reactions in the presence of K2CO3 in MeCN at 90°C for 60h afforded only imidazo[l,2-n]pyrimidine-3-carboxylates. 

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See also in sourсe #XX -- [ , ]

See also in sourсe #XX -- [ , ]

See also in sourсe #XX -- [ , ]

See also in sourсe #XX -- [ , ]

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