Copper-Catalyzed Amino Lactonization and Amino Oxygenation of Alkenes Using <i>O</i>-Benzoylhydroxylamines
作者:Brett N. Hemric、Kun Shen、Qiu Wang
DOI:10.1021/jacs.6b02840
日期:2016.5.11
A copper-catalyzed amino lactonization of unsaturated carboxylic acids has been achieved as well as the analogous intermolecular three-component amino oxygenation of olefins. The transformation features mild conditions and a remarkably broad substrate scope, offering a novel and efficient approach to construct a wide range of amino lactones as well as 1,2-amino alcohol derivatives. Mechanistic studies
Analysis of the13C and1H spectra of mixtures of benzylidene derivatives
作者:J. C. Bradley、A. J. Williams
DOI:10.1002/mrc.1260320812
日期:1994.8
The 1H and 13C NMR spectra of methyl (E)‐2,3,‐diphenylprop‐2‐enoate and methyl (E)‐2‐(2‐phenylethenyl) benzoate resulting from the electrocyclic ring opening of benzocyclobutenone starting materials have been assigned. A combination of direct detection 2D NMR techniques, COSY, HETCOR and FLOCK, provided the assignments of the 1H and 13C resonances.
stereochemistry of the reaction of cis- and trans-stilbene-2-carboxylic acids with chlorine and bromine, yielding the two diastereoisomeric 3-phenyl-4-halo-3:4-dihydroisocoumarins (III) and (IV) has been investigated. The reactions are entirely stereospecific and involve intramolecular attack by the carboxyl group on an intermediate carbonium or halonium ion. The lactones (III) and (IV) yield the two 3-(α-hydroxybenzyl)
Rhodium-catalyzed oxidative decarbonylative Heck-type coupling of aromatic aldehydes with terminal alkenes
作者:Lei Kang、Feng Zhang、Lin-Ting Ding、Luo Yang
DOI:10.1039/c5ra21610a
日期:——
rhodium-catalyzed oxidative decarbonylative Heck-type coupling of aromatic aldehydes with terminal alkenes to afford 1,2-disubstituted alkenes with good regio- and E-selectivity is developed. This reaction employs readily available aromatic aldehydes as the aryl electrophile counterpart and relies on selected acyl chloride as the crucial additive to activate the rhodium catalyst precursor.
Z E photoisomerization of benzylidenebenzocyclobutenones via ketene-allene intermediates. A laser flash photolysis study
作者:R. Boch、J.C. Bradley、T. Durst、J.C. Scaiano
DOI:10.1016/0040-4039(94)88151-0
日期:1994.1
∼26 μs and can be trapped with water and methanol. Trapping by the latter occurs with a rate constant of 1.2 × 104 M−1 s−1 and leads to the expected ester. In addition to Z E isomerization, product studies reveal the formation of dimeric products in very low quantum yields.
亚苄基苯并环丁烯酮I -E和I -Z通过乙烯酮-烯丙基II的中间体进行光诱导的异构化,该酮在乙腈中的寿命约为26μs,可以被水和甲醇捕获。后者的俘获以1.2×10 4 M -1 s -1的速率常数发生,并产生期望的酯。除ZE异构化外,产物研究还表明以非常低的量子产率形成了二聚体产物。