Copper-Mediated Fluoroalkylation Reactions with Iododifluoroacetamides: Controlling the Selectivity among Cross-Coupling, Intramolecular Cyclization, and Homocoupling Reactions
摘要:
Cu-mediated fluoroalkylation reactions with iododifluoroacetamides I 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 R-1 = alkyl and R-2 = aryl groups, or when R-1 = R-2 = aryl groups, the intramolecular cyclization products 3 can be formed predominantly; and (c) in the absence of aryl/alkenyl iodides, and when R-1 = R-2 = alkyl groups, or when R-1 = H and R-2 = 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.
Fear et al., Journal of the Chemical Society, 1956, p. 3199,3202
作者:Fear et al.
DOI:——
日期:——
Copper-Mediated Fluoroalkylation Reactions with Iododifluoroacetamides: Controlling the Selectivity among Cross-Coupling, Intramolecular Cyclization, and Homocoupling Reactions
作者:Jieming Zhu、Wei Zhang、Laijun Zhang、Jun Liu、Ji Zheng、Jinbo Hu
DOI:10.1021/jo1005262
日期:2010.8.20
Cu-mediated fluoroalkylation reactions with iododifluoroacetamides I 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 R-1 = alkyl and R-2 = aryl groups, or when R-1 = R-2 = aryl groups, the intramolecular cyclization products 3 can be formed predominantly; and (c) in the absence of aryl/alkenyl iodides, and when R-1 = R-2 = alkyl groups, or when R-1 = H and R-2 = 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.