O-炔丙基β-酮酸酯和O-烯丙基β-酮酸酯的高效催化不对称克莱森重排反应是在温和的反应条件下完成的。在存在手性N,N'-二氧化物/ Ni II配合物的情况下,通常以良好的收率(高达99%)和高的非对映选择性(高达90%)获得各种各样的烯丙基/烯丙基取代的全碳季β-酮酸酯。至99:1 dr)的对映选择性(高达99%ee)。
This paper reports on the stoichiometric and catalytic allylic substituion reactions involving molybdenum complexes and the sensitivity of regioselectivity toward the nature of the ligands on molybdenum. Results indicated that the allylicalkylation catalyzed by molybdenum forms a useful and frequently complementary alternative to the palladium-catalyzed reaction. For example, regioselectivity appears
本文报道了涉及钼配合物的化学计量和催化烯丙基取代反应以及区域选择性对钼配体性质的敏感性。结果表明,由钼催化的烯丙基烷基化形成了钯催化反应的有用且经常互补的替代方案。例如,在 Mo 的情况下,区域选择性似乎对配体变化更敏感。在 ..pi..-allyl 片段的一级碳和二级碳上的连接选择性更高。存在。另一方面,这些反应需要更高的温度和更长的时间。需要对这种钼化学进行更彻底的评估,以描绘其全部潜力。
Regiochemical diversity in allylic alkylations via molybdenum catalysts
作者:Barry M. Trost、Mark Lautens
DOI:10.1016/s0040-4020(01)87666-3
日期:1987.1
the more substituted end of an allyl system regardless of the positional identity of the initial leaving group exists. With β-ketoesters, substrates which possess a secondary and a primary carbon in the allyl unit lead to preferential attack at the secondary carbon. However, substrates that possess a tertiary and a primary carbon at the termini lead to attack at the primary carbon. Anions derived from
Regio- and Enantioselective Rhodium-Catalyzed Allylic Alkylation of Racemic Allylic Alcohols with 1,3-Diketones
作者:Sheng-Biao Tang、Xiao Zhang、Hang-Fei Tu、Shu-Li You
DOI:10.1021/jacs.8b05126
日期:2018.6.20
Highly regio- and enantioselective rhodium-catalyzed allylicalkylation of 1,3-diketones with racemic secondary allylic alcohols is reported. In the presence of a Rh-catalyst derived from the Carreira (P, olefin)-ligand and TFA as an additive, chiral branched α-allylated 1,3-diketones could be obtained in good to excellent yields, with excellent regio- and enantioselectivity ( b/ l > 19/1, 86-98% ee)