diazoacetates with cysteine residues that enabled metal‐free, S−H functionalization under visible‐light conditions. Moreover, this process could be intensified by a continuous‐flow photomicroreactor on the acceleration of the reaction (6.5 min residence time). The batch and flow protocols described were applied to obtain a wide range of functionalized cysteine derivatives and cysteine‐containing dipeptides
Rapid Assembly of Saturated Nitrogen Heterocycles in One-Pot: Diazo-Heterocycle “Stitching” by N-H Insertion and Cyclization
作者:Alexander J. Boddy、Dominic P. Affron、Christopher J. Cordier、Emma L. Rivers、Alan C. Spivey、James A. Bull
DOI:10.1002/anie.201812925
日期:2019.1.28
Methods that providerapidaccess to new heterocyclic structures in biologically relevant chemical space provide important opportunities in drug discovery. Here, a strategy is described for the preparation of 2,2‐disubstituted azetidines, pyrrolidines, piperidines, and azepanes bearing ester and diverse aryl substituents. A one‐pot rhodium catalyzed N–H insertion and cyclization sequence uses diazo
diazocompounds was developed to give gem-difluoroolefins, which constitutes a fast practical pathway to achieve hindered gem-difluoroolefins. The cross-coupling between difluorocarbene and aryl diazoacetates proceeded smoothly in the presence of a copper source, whereas its coupling with diaryl diazomethanes occurred well under metal-free conditions. A mechanism involving a copper–difluorocarbene complex
An efficient Brønsted acid-catalyzed Friedel-Crafts-type alkylation of arenes with α-aryl diazoacetates has been developed. This protocol enables effective access to various highly functionalized diarylmethane derivatives in moderate to high yields. Moreover, the product of selected diaryl acetate could be transformed to β, β-diaryl substituted γ-butyrolactone.
作者:Pu-Sheng Wang、Hua-Chen Lin、Xiao-Le Zhou、Liu-Zhu Gong
DOI:10.1021/ol501356z
日期:2014.6.20
The first allylic C–H olefination with α-diazo esters synergistically catalyzed by a palladium(II) complex and (salen)CrCl has been established to directly generate conjugated polyene derivatives in moderate to high yields and with excellent stereoselectivities.