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。
The reduction of the carbonyl group in acylated trifluoroethyl alkanesulfonates follows the Felkin-Ahn selectivity, and the so-formed diastereomeric β-hydroxysulfonyl intermediates undergo syn- and anti-fragmentation, depending on the reaction conditions. In effect, isomeric E- and Z-alkenes are formed in a stereodivergent manner, which mimics the mechanistic manifold of the Peterson olefination.
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
Rh(<scp>iii</scp>)-Catalyzed allylic C–H amidation of unactivated alkenes with <i>in situ</i> generated iminoiodinanes
作者:Pinki Sihag、Masilamani Jeganmohan
DOI:10.1039/d1cc02283k
日期:——
Rh(iii)-catalyzed direct allylic C–H amidation of substituted alkenes by in situ generated iminoiodinanes in a highly atom- and step-economical manner is demonstrated.
Copper-Catalyzed Alkene Arylation with Diaryliodonium Salts
作者:Robert J. Phipps、Lindsay McMurray、Stefanie Ritter、Hung A. Duong、Matthew J. Gaunt
DOI:10.1021/ja3039807
日期:2012.7.4
synthetic organic chemistry. We report a new approach to alkene arylation using diaryliodoniumsalts and Cu catalysis. Using a range of simple alkenes, we have shown that the product outcomes differ significantly from those commonly obtained by the Heck reaction. We have used these insights to develop a number of new tandem and cascade reactions that transform readily available alkenes into complex arylated