Purine studies. Part 24. Preparation of 1,6- and 7,8-dihydro-derivatives of 8-trifluoromethylpurines by reduction

Abstract

8-Trifluoromethylpurine (1a) was converted by catalytic hydrogentation entirely to the 1,6-dihydro-derivative (3a), whereas 9-methyl-8-trifluoromethypurine (1b) produced a 2 : 1 mixture of the 1,6-(3b) and 7,8-(5) dihydroderivatives. The new hydrogenated purines are characterised by unusual stability. Physical properties are discussed and compared with those of analogues from several other heterocyclic series.