Topological Study of Mechanistic Diversity in Conjugated Fatty Acid Biosynthesis
作者:Palash Bhar、Darwin W. Reed、Patrick S. Covello、Peter H. Buist
DOI:10.1002/anie.201202080
日期:2012.7.2
Variations on an oxidative theme: The precision with which FAD2‐type desaturases carry out CH activation reactions on flexible lipidic substrates is astonishing. The conformational space available within the active site of these enzymes has been explored using deuterium‐labeled substrates, and evidence for a novel quasi‐eclipsed conformer has been uncovered. The scheme shows some prototypical substrate
Diastereoselective Three-Component 3,4-Amino Oxygenation of 1,3-Dienes Catalyzed by a Cationic Heptamethylindenyl Rhodium(III) Complex
作者:Finn Burg、Tomislav Rovis
DOI:10.1021/jacs.1c09276
日期:2021.11.3
tool to rapidly access β-amino alcohols–a privilegedmotif ubiquitous in natural products, pharmaceuticals and agrochemicals. Although a variety of expedient methods are established for simple alkenes, selective amino oxygenation of 1,3-dienes is less explored. Within this context, methods for the oxyamination of 1,3-dienes that are selective for the internal position remain unprecedented. We herein report
Micellar effects in the nitrous acid deamination reaction of (R)-[1-2H]-1-octanamine
作者:Daniel Brosch、Wolfgang Kirmse
DOI:10.1021/jo00057a025
日期:1993.2
The nitrous acid deamination of 1-octanamine (1) afforded mixtures of isomeric octenes, octanols, and octyl nitrites. The aggregation of 1.HClO4 in micelles induced the formation of dioctyl ethers and of 1-nitrooctane as additional products. In homogeneous solution (submicellar aqueous conditions or HOAc), [1-H-2]-1-octanol was obtained from [1-H-2]-1 with ca. 95% inversion of configuration. Above the critical micelle concentration, the enantiomeric purity of [1-H-2]-1-octanol decreased while [1-H-2]-1-nitrooctane was formed with ca.90% retention of configuration. 1-Octyl..NO2 radical pairs, rather than ion pairs, are likely to intervene on the retentive route to 1-nitrooctane and 1-octyl nitrite. Equilibration, via NO exchange, of (R)-[1-H-2]-1-octyl nitrite with the more abundant (S)-[1-H-2]-1-octanol is thought to account for the diminished ee of both products.
Unveiling the Role of Molecule-Assisted Homolysis: A Mechanistic Probe into the Chemistry of a Bicyclic Peroxide
作者:Randi K. Gbur、R. Daniel Little
DOI:10.1021/jo300297u
日期:2012.3.2
Unlike the reaction of aryl-substituted diazenes, pyrolysis of alkyl-substituted diazenes in the presence of molecular oxygen generates an unexpectedly complex product mixture. Using deuterium labeling studies, in conjunction with quantum calculations, a reasonable mechanistic hypothesis for the decomposition of the resultant [3.3.0] peroxide, and subsequent formation of the keto-alcohol and Z-configured alpha,beta-unsaturated keto-aldehyde, is proposed. Surprisingly, molecule-assisted homolysis plays a key role in this transformation, the details of which are discussed herein.
KALVIN, D. M.;WOODARD, R. W., TETRAHEDRON, 1984, 40, N 18, 3387-3392