The synthesis of 5-trifluoromethyl-substituted (Z)-N,N-dimethyl-N′-(pyrazin-2-yl)formimidamides via the iodination of 2-aminopyrazines with Selectfluor/LiI followed by a domino trifluoromethylation with FSO₂CF₂CO₂Me and a condensation with DMF in the presence of CuI is realized under mild conditions. This three-step method offers CF₃-substituted (Z)-N,N-dimethyl-N′-(pyrazin-2-yl)formimidamides in yields of 55–70% and with high regioselectivities. LiI serves as an iodine source, whilst DMF functions as both a solvent and a condensation reagent. The regioselectivity of these trifluoromethylation reactions is strongly dependent upon the substituent pattern on the 2-aminopyrazines. A possible mechanism for this method is also discussed.

用 Selectfluor/LiI 碘化 2-氨基吡嗪，然后用 FSO ₂ CF ₂进行多米诺三氟甲基化，合成 5-三氟甲基取代的 ( Z )- N , N -二甲基- N '-(pyrazin-2-yl)formimidamides在温和条件下，在 CuI 存在下实现CO _{2 Me 和与 DMF 的缩合。}这种三步法提供了 CF ₃ -取代的 ( Z )- N , N -二甲基- N'-(pyrazin-2-yl)formimidamides 的产率为 55-70% 并具有高区域选择性。LiI 用作碘源，而 DMF 用作溶剂和缩合试剂。这些三氟甲基化反应的区域选择性很大程度上取决于 2-氨基吡嗪上的取代基模式。还讨论了这种方法的可能机制。