Such chiral phosphine–internal olefin hybrid type ligands as N-1-adamantyl-N-cinnamylaniline derivatives 1 with C(aryl)–N(amine) bond axial chirality were synthesized and utilized for the palladium-catalyzed asymmetric allylicalkylation of indoles to afford the desired products in high enantioselectivities (up to 98% ee).
Versatile Chiral Bidentate Ligands Derived from α-Amino Acids: Synthetic Applications and Mechanistic Considerations in the Palladium-Mediated Asymmetric Allylic Substitutions
to other amino groups in the amidine skeleton and the production of other types of ligands, are possible using the precursor compounds of 7a. Thus, novel chiral ligands 7c,d, 8, 11, and 13, which provide sterically and electronically different chiral circumstances, were prepared and used for the palladium-mediated asymmetric allylic substitutions of both acyclic and cyclic compounds. In these reactions
1,1,1,3,3,3-Hexafluoro-2-propanol (HFIP)-Assisted Catalyst-Free Sulfonation of Allylic Alcohols with Sulfinyl Amides
作者:Zhen Luo、Zheng-Qiang Liu、Ting-Ting Yang、Xin Zhuang、Chuan-Ming Hong、Fei-Fei Zou、Zhi-Yong Xue、Qing-Hua Li、Tang-Lin Liu
DOI:10.1021/acs.orglett.1c04206
日期:2022.1.21
A highly regioselective and catalyst-free sulfonation of allylic alcohols with sulfinyl amides has been realized. Such a mix-and-go procedure provides a convenient approach to synthetically various allylic sulfones under mild reaction conditions. Furthermore, this novel reaction shows ample substrate scope and outstanding functional group tolerance and could also be scaled-up. Meanwhile, it is the
Palladium-catalyzedasymmetricallylic alkylation of 1,3-diphenyl-2-propenyl acetate (8a) with a dimethyl malonate–BSA–LiOAc system has been successfully carried out in the presence of novel chiral phosphine–oxazinane ligands such as 5b in good yields with good enantioselectivities (up to 95% ee).
Enantioselective allylic substitutions using ketene silyl acetals catalyzed by a palladium–chiral amidine complex
作者:Akihito Saitoh、Kazuo Achiwa、Toshiaki Morimoto
DOI:10.1016/s0957-4166(98)00045-7
日期:1998.3
Enantioselective allylic substitutions using ketene silyl acetals 3 as a nucleophile have been explored. In the asymmetric reactions of 1,3-diphenylprop-2-enyl pivalate 2 catalyzed by the Pd(0)–chiral amidine 1 complex, excellent levels of stereocontrol are achieved along with good conversions, demonstrating that ketene silyl acetals are able to expand the scope of asymmetric allylic alkylations. The