(81–94%). The dihydropyridines were oxidized by oxygen to give 4-alkyl(aryl)pyridines (38–68%). Grignard reagents also reacted with 1-t-butyldimethylsilylpyridinium triflate with almost complete regioselectivity (>99%) to afford the corresponding 1,4-dihydropyridines, which were easily oxidized by oxygen to give 4-substituted pyridines in higher yields than above (58–70%).
RCu·
BF3 与
1-乙氧基羰基
氯化
吡啶在4-位反应,几乎完全区域选择性(>99%),以高产率(81-94%)得到相应的1,4-二
氢吡啶衍生物。
二氢吡啶被
氧氧化得到4-烷基(芳基)
吡啶(38-68%)。
格氏试剂还与 1-叔丁基二
甲基甲
硅烷基
吡啶鎓
三氟甲磺酸盐反应,以几乎完全的区域选择性(>99%)得到相应的 1,4-
二氢吡啶,它们很容易被
氧气氧化得到 4-取代的
吡啶,产率高于上述(58- 70%)。