251295-04-2Relevant articles and documents
Ortho-hydroxyalkylation of aminopyridines: A novel approach to heterocycles
Zakrzewski, Peter,Gowan, Mathew,Trimble, Laird A.,Lau, Cheuk K.
, p. 1893 - 1902 (2007/10/03)
Reaction of 6-substituted N-alkyl-3-aminopyridines with aldehydes in the presence of dichlorophenylborane gives selectively 2-hydroxyalkyl-3- aminopyridines. Dehydration of the latter under pyrolytic or Lewis acid conditions generates a quinone methide imine intermediate which can undergo electrocyclic or [4+2] cycloaddition reactions to give naphthyridines, dihydronaphthyridines or tetrahydronaphthyridines. Palladium-catalyzed cyclization of the 2-(1-hydroxyallyl)-3-aminopyridines gives the corresponding 4-azaindoles.