ADDITION OF ELECTROPHILIC RADICALS TO CAFFEINE: SYNTHETIC ASPECTS AND INFLUENCE OF THE PEROXIDIC INITIATORS

Article abstract of DOI:10.1016/0040-4020(89)80102-4

Primary and secondary electrophilic radicals such as: ^.CHRCO2CH3 (R=H, CH3, CO2CH3) and tertiary ^.CCl3 radical were added directly at C-8 of, th model purine compound, caffeine to give the corresponding 8-substituted derivatives in fairly good yields.Unexpected reaction of caffeine with oxy radicals from the initiators (PhCO2^., t-BuOO^.) gave rise to C-5 substituted 1,3,7-trimethyl-5,7-dihydrouric acid derivatives (C-5-R=CCl3, CH3, C(CH3)2CO2CH3) and to the spirodihydantoin C-8 adduct derivative of caffeine 11.