Valuable Synthetic Building Blocks: Useful 2-Substituted 5-Amino­pyrimidines from a Stable Precursor

An efficient large-scale synthesis of 5-aminopyrimidine derivatives is described. The dihexafluorophosphate salt of a vinamidinium cation important in 5-aminopyrimidine synthesis has been prepared as a stable, easily purified intermediate. It has been used to prepare several 2-functionalized aminopyrimidines, valuable as synthetic building blocks.