Tandem <i>N</i>,<i>N</i>-Dialkylation Reaction of <i>N</i>-Trimethylsilyl α-Iminoesters Utilizing an Umpolung Reaction and Characteristics of the Silyl Substituent: Synthesis of Pyrrolidine, Piperidine, and Iminodiacetate
with organometallics gave directly N-alkylaminoesters in high yields without the need for removing a protecting group at the nitrogen atom. Efficient syntheses of pyrrolidines, piperidines, and iminodiacetate derivatives were also developed via tandem N,N- or N,C-dialkylation reactions utilizing characteristics of the silyl substituent. Furthermore, under the influence of silica gel, the addition of
Iron‐Catalyzed Cleavage Reaction of Keto Acids with Aliphatic Aldehydes for the Synthesis of Ketones and Ketone Esters
作者:Fangyuan Zhou、Lesong Li、Kao Lin、Feng Zhang、Guo‐Jun Deng、Hang Gong
DOI:10.1002/chem.202000114
日期:2020.4
The radical-radical coupling reaction is an important synthetic strategy. In this study, the iron-catalyzed radical-radical cross-coupling reaction based on the decarboxylation of keto acids and decarbonylation of aliphaticaldehydes to obtain valuable aryl ketones is reported for the first time. Remarkably, when tertiary aldehydes were used as carbonyl sources, ketone esters were selectively obtained
Amino Acid Salt Catalyzed Asymmetric Synthesis of 1,2-Diols with A Quaternary Carbon Center
作者:Jun Jiang、Quanquan Wu、Shulei Liu、Fangyuan Wang、Qingqing Li、Kangli Cheng、Juan Li
DOI:10.1055/s-0035-1560179
日期:——
which demand for both good diastereo- and enantioselectivity. As part of our continuous effort to explore the unique catalytic activities of amino acid salts in the asymmetric synthesis, herein, we wish to report an amino acidsaltcatalyzed direct aldolreaction between hydroxyacetone and α-keto esters, which afforded the 1,2-diols with a quaternary carbon center in high diastereo- and enantioselectivities
Chemo- and Enantioselective Brønsted Acid-Catalyzed Reduction of α-Imino Esters with Catecholborane
作者:Dieter Enders、Andreas Rembiak、Bianca Anne Stöckel
DOI:10.1002/adsc.201300352
日期:2013.7.8
The chemo‐ and enantioselectivereduction of α‐imino esters with catecholborane has been developed employing 10 mol% of an enantiopure BINOL‐based phosphoric acid as organocatalyst. Various differently substituted aromatic α‐amino acid derivatives can be achieved in almost quantitative yields and very good to excellent enantioselectivities of up to 96% ee under mild reaction conditions.
A deuterium‐labelingreaction of nitroalkanes in deuterium oxide and the subsequent nitroaldol reaction have been accomplished under basic and organocatalytic conditions to provide the deuterium‐labeled β‐nitroalcohols in high yields and high deuterium contents. β‐Deuterated β‐nitroalcohols could be smoothly obtained from the reaction of nitroalkanes and various electrophiles using the easily‐removal