使用Ni或Fe催化剂成功地实现了S N 2-选择性格利雅(Grignard)与伯烯丙基二苯基磷酸酯的偶联。与之形成鲜明对比的是,催化量的CuCN·2LiCl促进了S N 2'-选择性偶联反应。在铜催化剂的存在下,立体化学均一的γ-二取代的烯丙基格氏试剂在较少取代的烯丙基末端(α-位)与烯丙基磷酸二苯酯选择性地反应,而不会失去双键的几何形状。
An efficient cross-coupling reaction of N-allylicsulfonimides with organozincreagents has been developed. In the presence of 1 mol-% of Pd 2 (dba) 3 , a range of N-allylicsulfonimides smoothly couple with various organozincreagents at roomtemperature to give the corresponding (E)-alkene products in moderate to excellent yields and with good to exclusive α-selectivity. It is noteworthy that allyl
carbonyl group, cyano group) in an alkyl halide facilitates its cross-coupling reaction with various diorganozincs in the presence of Ni(acac)(2) (7.5-10 mol % in THF/NMP mixtures). These results were used to develop a new general cross-coupling reaction between functionalized diorganozincs and alkyliodides using m- or p-trifluoromethylstyrene as a reaction promotor and Ni(acac)(2) as a catalyst (7.5-10
Copper catalyzed magnesium-Barbier reaction for γ-selective alkyl–allyl coupling
作者:Ender Erdik、Melike Koçoğlu
DOI:10.1016/j.tetlet.2007.04.060
日期:2007.6
CuCN catalyzed alkyl-allyl coupling under magnesium-Barbier conditions occurs regioselectively and affords predominantly the gamma-products in good to high yields. This one-pot CuCN catalyzed reaction utilising Mg, an alkyl halide and an allylic substrate in THF at room temperature provides an easy alternative to the classical CuCN catalyzed gamma-allylation of alkyl Grignard reagents. (c) 2007 Elsevier Ltd. All rights reserved.
Grignard Reagents and Unsaturated Ethers. II.<sup>1</sup> Reaction of Grignard Reagents with β,γ-Unsaturated Ethers<sup>2</sup>
作者:Carl M. Hill、Lonnie Haynes、Doris E. Simmons、Mary E. Hill