157922-22-0Relevant articles and documents
Disubstituted pyridines: The double-coupling approach
Handy, Scott T.,Wilson, Thomas,Muth, Aaron
, p. 8496 - 8500 (2007)
(Chemical Equation Presented) A one-pot procedure leading to disubstituted pyridines from the starting dibromopyridines is described. Key features include the ability to couple a range of aryl and even alkenylboronic acids at the 2,3 and/or 2,5 positions
Selectivities in the formation of pyridines and pyrimidines by ammonia-induced cyclocondensations of vinamidiniums
Natarajan Balasubrahmanyam,Jeyashri, Bommuswamy,Narayanan Namboothiri, Irishi N.
, p. 8127 - 8142 (2007/10/02)
Arylvinamidines (2-, 3- or 4-aryl-4-(N,N-dimethyl)amino-1-azabuta-1,3-dienes), generated from 1,1,5,5-tetramethyl-2- or 3-phenyl-1,5-diazapentadienium salts, cyclocondense orientation-specifically under two regioselections forming 1-4'+4-3' and 1-2'+4-1' bonds on exposure to ammonia. The initial cyclates aromatise eliminatively to give mixtures of diarylpyridines and arylpyrimidines. The 2-arylvinamidines do not participate as 2-centre reactants and their 4-aryl isomers not as 4-centre reactants in the cyclocondensations which appear to be stepwise and not concerned. Reasons for the selective participation appear to be that the required eliminations from the initial cyclates are disfavoured in the first case and that a geometric factor prevents cyclate-formation in the second.
