Structure-Based Insight into the Asymmetric Bioreduction of the CC Double Bond of α,β-Unsaturated Nitroalkenes by Pentaerythritol Tetranitrate Reductase
作者:Helen S. Toogood、Anna Fryszkowska、Victoria Hare、Karl Fisher、Anna Roujeinikova、David Leys、John M. Gardiner、Gill M. Stephens、Nigel S. Scrutton
DOI:10.1002/adsc.200800561
日期:——
Biocatalytic reduction of alpha- or beta-alkyl-beta-arylnitroalkenes provides a convenient and efficient method to prepare chiral substituted nitroalkanes. Pentaerythritoltetranitratereductase (PETN reductase) from Enterobacter cloacae st. PB2 catalyses the reduction of nitroolefins such as 1-nitrocyclohexene (1) with steady state and rapid reaction kinetics comparable to other old yellow enzyme
Biocatalytic Asymmetric Alkene Reduction: Crystal Structure and Characterization of a Double Bond Reductase from <i>Nicotiana tabacum</i>
作者:David J. Mansell、Helen S. Toogood、John Waller、John M. X. Hughes、Colin W. Levy、John M. Gardiner、Nigel S. Scrutton
DOI:10.1021/cs300709m
日期:2013.3.1
biocatalysis for the asymmetric reduction of activatedC═C is a powerful tool for the manufacture of high-value chemical commodities. The biocatalytic potential of “-ene” reductasesfrom the OldYellowEnzyme (OYE) family of oxidoreductases is well-known; however, the specificity of these enzymes toward mainly small molecule substrates has highlighted the need to discover “-ene” reductasesfrom different enzymatic
We leverage the slow liberation of nitrogen dioxide from a newly discovered, inexpensive succinimide-derived reagent to allow for the C-H diversification of alkenes and alkynes. Beyond furnishing a library of aryl β-nitroalkenes, this reagent provides unparalleled access to β-nitrohydrins and β-nitroethers. Detailed mechanistic studies strongly suggest that a mesolytic N-N bond fragmentation liberates
common and versatile reagent. Its synthesis from olefin is generally limited by the formation of mixture of cis and trans compounds. Here we report that silver nitrite (AgNO2) along with TEMPO can promote the regio- and stereoselective nitration of a broad range of olefins. This work discloses a new and efficient approach wherein starting from olefin, nitroalkane radical formation and subsequent transformations
硝基烯烃是一种常见且用途广泛的试剂。它从烯烃合成通常受到顺式和反式化合物混合物的形成的限制。在这里,我们报告亚硝酸银 (AgNO2) 与 TEMPO 一起可以促进范围广泛的烯烃的区域和立体选择性硝化。这项工作公开了一种新的有效方法,其中从烯烃开始,硝基烷烃自由基形成和随后的转化以立体选择性方式导致所需的硝基烯烃。
Highly Enantioselective Construction of Trifluoromethylated All-Carbon Quaternary Stereocenters via Nickel-Catalyzed Friedel–Crafts Alkylation Reaction
A highlyenantioselectiveFriedel-Craftsalkylation reaction of indoles with β-CF(3)-β-disubstituted nitroalkenes was achieved using a Ni(ClO(4))(2)-bisoxazoline complex as a catalyst, which afforded indole-bearing chiral compounds with trifluoromethylated all-carbon quaternary stereocenters in good yields with excellent enantioselectivities (up to 97% ee). The transformation of one of the products