Department of Applied Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology , O-okayama, Meguro-ku, Tokyo 152-8552, Japan.
Org Lett. 2015 Oct 2;17(19):4882-5. doi: 10.1021/acs.orglett.5b02438.
Difluoromethylation on sp(3) carbon of various nitrile compounds with lithium base and fluoroform (CF3H), which is an ideal difluoromethylating reagent, is shown to provide the α-difluoromethylated nitrile products with an all-carbon quaternary center in moderate to high yields. The Ruppert-Prakash reagent (CF3TMS) is also applicable to the reaction, affording the α-siladifluoromethylated nitrile products, which can be utilized for sequential carbon-carbon bond-forming reactions. These reactions using 1.1 equiv of lithium base, 1.5-2.0 equiv of CF3H or CF3TMS, and easily accessible nitrile derivatives are completed in only a few minutes, resulting in the formation of valuable difluoromethylated compounds.
各种腈类化合物的 sp(3)碳原子与碱金属锂和氟仿(CF3H)发生二氟甲基化反应,氟仿是一种理想的二氟甲基化试剂,该反应以中等到高产率得到了具有全碳季碳原子的α-二氟甲基化腈产物。Ruppert-Prakash 试剂(CF3TMS)也适用于该反应,得到α-硅基二氟甲基化腈产物,该产物可用于连续的碳-碳键形成反应。这些反应使用 1.1 当量的碱金属锂、1.5-2.0 当量的 CF3H 或 CF3TMS,以及易于获得的腈衍生物,仅在几分钟内即可完成,形成有价值的二氟甲基化化合物。