Patent ID: 6960662

Claim:
A process for preparing a 2-(pyridin-4-ylamino)-pyrido[2,3-d]pyrimidine of Formula II comprising reacting a 4-aminopyridine of the formula with a 2-(4-imino-4H-pyridin-1-yl)-pyrido[2,3-d]pyrimidine of Formula I in the presence of a base: wherein R′ and R″ independently are hydrogen, C 1 -C 6 alkyl, C 1 -C 6 alkoxy, or phenyl; R 2 is (CH 2 ) n Ph, where Ph is phenyl or substituted phenyl, and n is 0, 1, 2, or 3; heteroaromatic; cycloalkyl; C 1 -C 6 alkyl; or C 2 -C 6 alkenyl; where the alkyl and alkenyl groups may be substituted by NR 5 R 6 , phenyl, substituted phenyl, or cycloalkyl, and where R 5 and R 6 are independently C 1 -C 6 alkyl; C 2 -C 6 alkenyl; (CH 2 ) n Ph where Ph is phenyl or substituted phenyl, and n is 0, 1, 2, or 3; cycloalkyl, or heteroaromatic, or R 5 and R 6 taken together with the nitrogen to which they are attached can complete a nitrogen containing ring having 3 to 7 carbon atoms and optionally containing 1 or 2 additional heteroatoms selected from the group consisting of nitrogen, substituted nitrogen, oxygen, and sulfur; and Ar is phenyl, substituted phenyl, or heteroaromatic.