Solid phase synthesis of purines from pyrimidines

In this paper the solid phase synthesis of various substituted purines is described starting from 4,6-dichloro-5-nitropyrimidine, The 4,6-dichloro-5-nitropyrimidine was coupled to Rink amide resin followed by displacement of the second chloride by an amino compound. Reduction of the nitro compound proved to be problematic but was achieved using lithium aluminum hydride/aluminum trichloride. The diamines (13) were then elaborated to purines by three different routes.</p