Several new derivatives of adenine, purine, and theophylline containing the (CF₃)₂CH group connected to a nitrogen atom of the imidazole ring were prepared by the reaction of 2,2,4,4-tetrakis(trifluoromethyl)-1,3-dithietane (1) with the corresponding substrates, resulting in the selective alkylation of one of the nitrogen atoms of the imidazole ring. The reaction proceeds under mild conditions in a polar solvent, giving the alkylated products in 47–78% yield. While for purine and 4- and 5-azabenzimidazole, the reaction led to a mixture of two isomers, the reaction of adenine and the corresponding 2-fluoro derivative was regioselective, resulting in the formation of only one isomer in each case. The alkylation of theophylline led to the formation of a new derivative of caffeine.

中文翻译：

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含六氟异丙基的嘌呤和腺嘌呤的合成

通过2,2,4,4-四（三氟甲基）-1,3的反应制备了几种新的腺嘌呤，嘌呤和茶碱的衍生物，它们含有与咪唑环的氮原子连接的（CF ₃）₂ CH基团。 -dithietane（1）与相应的底物结合，导致咪唑环的一个氮原子选择性烷基化。反应在温和条件下在极性溶剂中进行，烷基化产物的收率在47％至78％之间。对于嘌呤和4-和5-氮杂苯并咪唑，该反应导致两种异构体的混合物，腺嘌呤与相应的2-氟衍生物的反应是区域选择性的，导致在每种情况下仅形成一种异构体。茶碱的烷基化导致咖啡因的新衍生物的形成。