PROCESS FOR PREPARING 3,7-DIALKYL XANTHINES

摘要

3.7 - dialkylxantiny are prepared from the corresponding 3 - alkylxanthinu016f by an alkylating agent in the presence of quaternary aminiovu00e9 or / and fosfoniovu00e9 compounds and, where appropriate, additional polyethers in dvoufu00e1zovu00e9 smu011bsi.u0155