1549-51-5Relevant articles and documents
Copper-mediated fluoroalkylation reactions with iododifluoroacetamides: Controlling the selectivity among cross-coupling, intramolecular cyclization, and homocoupling reactions
Zhu, Jieming,Zhang, Wei,Zhang, Laijun,Liu, Jun,Zheng, Ji,Hu, Jinbo
experimental part, p. 5505 - 5512 (2010/11/17)
Cu-mediated fluoroalkylation reactions with iododifluoroacetamides 1 have been systematically investigated. It was found that three types of reactions may coexist in Cu-mediated reactions between iododifluoroacetamides and aryl/alkenyl iodides: cross-coupling, intramolecular cyclization, and homocoupling reactions. The selectivity among these three types of reactions could be controlled by tuning the substituents on the nitrogen atom of iododifluoroacetamides, and/or by removing the cross-coupling reaction partner (aryl/alkenyl halides). The general rule is as follows: (a) in the presence of proper aryl/alkenyl iodides, the cross-coupling products 2 (or 6) are generally formed as the major products; (b) in the absence of aryl/alkenyl iodides, and when R1 = alkyl and R2 = aryl groups, or when R 1 = R2 = aryl groups, the intramolecular cyclization products 3 can be formed predominantly; and (c) in the absence of aryl/alkenyl iodides, and when R1 = R2 = alkyl groups, or when R 1 = H and R2 = alkyl, aryl groups, the homocoupling products 4 can be formed dominantly. Our experimental results also indicate that in many cases when cross-coupling, homocoupling, and intramolecular cyclization reactions coexist in the Cu-mediated reaction system, the reactivity decreases in the following order: cross-coupling > intramolecular cyclization > homocoupling.
