Highly efficient and facile synthesis of β-enaminones catalyzed by diphenylammonium triflate
作者:Ting-Ting Zhao、Jiang-Long Song、Feng-Qing Hong、Jian-Sheng Xia、Jian-Jun Li
DOI:10.1007/s11696-019-00838-2
日期:2019.11
The catalytic performance of diphenylammonium triflates as an organocatalyst in the synthesis of β-enaminones from various substituted β-diketones and amides (or amines) were evaluated. A wide range of β-enaminones were efficiently synthesized in good to excellent yields under mild reaction conditions. Applying diphenylammonium triflate (DPAT) as catalyst makes this protocol cost-effective, low corrosive and easy to handle.
Nickel-Catalyzed Asymmetric Transfer Hydrogenation of Olefins for the Synthesis of α- and β-Amino Acids
作者:Peng Yang、Haiyan Xu、Jianrong Steve Zhou
DOI:10.1002/anie.201407744
日期:2014.11.3
The field of asymmetric (transfer) hydrogenation of prochiral olefins has been dominated by noble metal catalysts based on rhodium, ruthenium, and iridium. Herein we report that a simple nickel catalyst is highly active in the transfer hydrogenation using formic acid. Chiral α‐ and β‐amino acid derivatives were obtained in good to excellent enantioselectivity. The key toward success was the use of
The rhodium-catalyzedasymmetrichydrogenation of various β-dehydroamino acid derivatives to give optically active β-amino acids has been examined. Chiral monodentate 4,5-dihydro-3H-dinaphthophosphepines, which are easily tuned and accessible in a multi-10-g scale, have been used as ligands. The enantioselectivity is largely dependent on the nature of the substituent at the phosphorous atom and on
Synthesis of β-Amino Acid Derivatives via Copper-Catalyzed Asymmetric 1,4-Reduction of β-(Acylamino)acrylates
作者:Yan Wu、Shan-Bin Qi、Fei-Fei Wu、Xi-Chang Zhang、Min Li、Jing Wu、Albert S. C. Chan
DOI:10.1021/ol200287z
日期:2011.4.1
A new set of reaction conditions has been established to facilitate the copper-catalyzed enantioselective 1,4-reduction of β-(acylamino)acrylates toward a selection of β-alkyl-β-amino acid derivatives in high yields and with uniformly high ee values (up to 99%) irrespective of the use of (E)- or (Z)-substrates.
Ru-Catalyzed Highly Enantioselective Hydrogenation of <i>β</i>-Alkyl-Substituted <i>β</i>-(Acylamino)acrylates
作者:Jing Wu、Xuanhua Chen、Rongwei Guo、Chi-hung Yeung、Albert S. C. Chan
DOI:10.1021/jo026675x
日期:2003.3.1
by Ru((R)-Xyl-P-Phos)(C(6)H(6))Cl(2) complex (cat. 1c) was achieved in up to 99.7% ee. Moderate to good enantioselectivities in the hydrogenation of corresponding (Z)-isomers in the presence of [Rh((R)-Xyl-P-Phos)(COD)]BF(4) (cat. 2c) were also obtained. The results demonstrated that the electronic and steric properties of the dipyridylphosphine ligands as well as the different transition metal ions