centers. The broad functionalgroup compatibility highlights the mildness of the present catalysis. Notably, we achieved successive β-functionalization and oxidation of aminoacid Schiff bases to afford dehydroalanine derivatives bearing tetrasubstituted carbon. A three-component cross-coupling reaction of an aminoacid Schiff base, alkyl bromides, and styrene derivatives demonstrated the high utility
Synthesis of Hindered Anilines: Three-Component Coupling of Arylboronic Acids, <i>tert</i>-Butyl Nitrite, and Alkyl Bromides
作者:David J. Fisher、James B. Shaum、C. Landon Mills、Javier Read de Alaniz
DOI:10.1021/acs.orglett.6b02523
日期:2016.10.7
The synthesis of sterically hindered amines has been a significant challenge in organic chemistry. Herein, we report a modular, three-component coupling that constructs two carbon–nitrogen bonds including a sterically hindered Csp3–N bond using commercially available materials. This process uses an earth-abundant copper catalyst and mild reaction conditions, allowing access to a variety of complex
Synthesis of Hindered α-Amino Carbonyls: Copper-Catalyzed Radical Addition with Nitroso Compounds
作者:David J. Fisher、G. Leslie Burnett、Rocío Velasco、Javier Read de Alaniz
DOI:10.1021/jacs.5b07860
日期:2015.9.16
The synthesis of sterically hindered anilines has been a significant challenge in organic chemistry. Here we report a Cu-catalyzed radical addition with in situ-generated nitrosocompounds to prepare sterically hindered amines directly from readily available materials. The transformation is conducted at room temperature, uses abundant copper salts, and is tolerant of a range of functional groups.
空间位阻苯胺的合成一直是有机化学中的一个重大挑战。在这里,我们报告了 Cu 催化的自由基加成与原位生成的亚硝基化合物,以直接从容易获得的材料制备位阻胺。转化在室温下进行,使用丰富的铜盐,并且可以耐受一系列官能团。
N-Heterocyclic Carbene-Catalyzed Radical Relay Enabling Synthesis of δ-Ketocarbonyls
作者:Kenji Ota、Kazunori Nagao、Hirohisa Ohmiya
DOI:10.1021/acs.orglett.0c01199
日期:2020.5.15
An NHC-catalyzed radical relay enabled the vicinal alkylacylation of alkenes using aldehydes and tertiary α-bromo esters as a versatile route to δ-keto esters bearing an all-carbon quaternary center at the position α to the ester. The protocol was applicable to the reaction of tertiary α-bromoamides to afford δ-keto amides. This protocol enabled the conversion of readily available starting materials
and aldehyde) in the C5 position with excellent regioselectivity (C5/others >20:1). Moreover, this protocol is also suitable for polycyclic aromatichydrocarbons and the more remote C8 position. Preliminary mechanistic studies show that the tertiary phosphine group plays two essential roles in the reaction: first, it assists the introduction of Ru–C bond at the C8 position; second, due to the induction