ALKYLATION OF SOME 6-SUBSTITUTED PURINES UNDER INTERPHASE CATALYSIS CONDITIONS

Article abstract of DOI:10.1007/BF00475484

The mixture of 9-, 3-, and 7-benzyl-6-substituted purines is formed in almost quantitative yield by the alkylation of 6-benzylamino-, 6-furfurylamino-, 6-methylthio-, and 6-chloropurine with benzyhalides in the biphasic system of the liquid-liquid or liquid-solid type in the presence of interphase catalysts (quarternary ammonium salts, 18-crown-6).The catalytic activity of the quarternary ammonium salts increases with the inrease in the lipophilicity of the cation.Taking the alkylation of 6-benzylaminopurine as an example, the possibility of the application of ''triphasic catalysis'' in the alkylation reaction of purines is indicated.The alkylation of 6-substituted purines with isopropylbromide proceeds regioselectively under the conditions of the interphase catalysis with the formation of the corresponding 9-isopropylpurines.