of racemic and branched monosubstituted allylicacetates by a ruthenium-catalyzed regioselective allylic etherification. The reaction was effectively catalyzed by the chiral ruthenium catalyst, which was generated by [RuCl2(p-cymene)]2 and (S,S)-iPr-pybox and a catalytic amount of TFA, and both the allylic etherification product and recovered allylicacetate were obtained as an enantiomerically enriched
Ni-Catalyzed Enantioselective Allylic Alkylation of <i>H</i>-Phosphinates
作者:Qing Zhang、Xu-Teng Liu、Yue Wu、Qing-Wei Zhang
DOI:10.1021/acs.orglett.1c02986
日期:2021.11.19
The asymmetric synthesis of P-stereogenic phosphinates through allylicalkylation of H-phosphinates has been developed. With H-phosphinates and allylic acetates as the starting materials, a variety of allylic P-chiral phosphinates were accessed in high enantioselectivities of up to 92% ee and generally high yields. In addition, a further study demonstrated the applicability of this protocol, including
的不对称合成P -stereogenic次膦酸盐通过的烯丙基烷基化ħ -phosphinates已经研制成功。以H-次膦酸盐和烯丙基乙酸酯为起始材料,以高达 92% ee 的高对映选择性和通常高产率获得了多种烯丙基P-手性次膦酸盐。此外,进一步的研究证明了该协议的适用性,包括在温和的反应条件下,使用有机锂试剂将手性产物从次膦酸盐放大合成和轻松转化为氧化膦。
Ni-Catalyzed Asymmetric Allylation of Secondary Phosphine Oxides
A nickel catalyzed asymmetric allylation of secondary phosphineoxides (SPO) for the synthesis of tertiary phosphineoxides (TPO) was realized with high enantioselectivity. The dynamic kinetic resolution of SPO was accomplished in the presence of nickel complex. By elucidating the absolute configurations of the reacted SPO starting material and the TPO product, we confirmed that the allylation reaction
Nickel/Photo-Cocatalyzed C(sp<sup>2</sup>)–H Allylation of Aldehydes and Formamides
作者:Pei Fan、Rui Wang、Chuan Wang
DOI:10.1021/acs.orglett.1c02938
日期:2021.10.1
nickel/photo-cocatalyzed C(sp2)–H allylation of aldehydes and formamides wherein both allyl acetates and allylalcohols can be used as the allylating agents. In this reaction, radical-type umpolung of the formyl moiety is enabled by tetrabutylammonium decatungstate as a hydrogen-atom-transfer photocatalyst, whereas nickel serves to cleave the C–O bond of allyl acetates or allylalcohols. The synergistic effect
Highly Regio‐ and Enantioselective Cu/Pd Co‐Catalyzed Allylic Alkylation of α‐pyridyl‐α‐fluoroesters: Construction of Quaternary C−F Stereocenters
作者:Xinlong Yan、Zongwei Li、Lin Fan、Jiashan Li、Guodu Liu
DOI:10.1002/asia.202300160
日期:2023.6
efficient synergistic Pd/Cu catalyst system for the highly regioselective asymmetric allylation of α-pyridyl-α-fluoroesters constructed straight-chain allyl products containing C−F quaternarystereocenter. A series of aryl- and aliphatic-substituted straight-chain allyl products were obtained in high yields, excellent enantioselectivities and E/Z-selectivities (up to 98% yield, 98 : 2 er, and >20 : 1