AlEt3-promoted eliminative ring-opening of β-hydroxy epoxides: highly stereoselective synthesis of terminal α-hydroxy olefins
摘要:
AlEt3-promoted eliminative ring-opening of beta-epoxy alcohols leading to alpha-hydroxy olefins is reported. This eliminative ring-opening reaction is shown to be highly stereoselective, thus providing an alternative asymmetric synthesis for a-hydroxy olefins. (C) 2003 Elsevier Ltd. All rights reserved.
Catalytic Multisite-Selective Acetoxylation Reactions at sp<sup>2</sup> vs sp<sup>3</sup> C–H Bonds in Cyclic Olefins
作者:Zhong-Lin Zang、Sheng Zhao、Shuklachary Karnakanti、Cheng-Lin Liu、Pan-Lin Shao、Yun He
DOI:10.1021/acs.orglett.6b02458
日期:2016.10.7
The first Pd-catalyzed multisite-selective acetoxylation reactions are disclosed at an unactivated alkene sp2 C–H bond versus secondary allylic sp3 C–H bond in cyclic olefins via the modulation of directing groups. The different directing groups overcome the key challenge in differentiating C–H bonds and provide a new controlling approach for site-specific C–H activation. A wide variety of substrates
Mechanistic Insight into Palladium-Catalyzed Cycloisomerization: A Combined Experimental and Theoretical Study
作者:Aroonroj Mekareeya、P. Ross Walker、Almudena Couce-Rios、Craig D. Campbell、Alan Steven、Robert S. Paton、Edward A. Anderson
DOI:10.1021/jacs.7b05436
日期:2017.7.26
bis-benzylidene ethylenediamine (bbeda) is a landmark methodology in transition-metal-catalyzed cycloisomerization. However, the mechanistic pathway by which this reaction proceeds has remained unclear for several decades. Here we describe mechanisticinvestigations into this reaction using enynamides, which deliver azacycles with high regio- and stereocontrol. Extensive 1H NMR spectroscopic studies and isotope
Pd-Catalyzed Conjunctive Cross-Coupling between Grignard-Derived Boron “Ate” Complexes and C(sp<sup>2</sup>) Halides or Triflates: NaOTf as a Grignard Activator and Halide Scavenger
作者:Gabriel J. Lovinger、Mark D. Aparece、James P. Morken
DOI:10.1021/jacs.6b12663
日期:2017.3.1
Catalytic enantioselectiveconjunctivecross-couplings that employ Grignard reagents are shown to furnish an array of nonracemic chiral organoboronic esters in an efficient and highly selective fashion. The utility of sodium triflate in facilitating this reaction is two-fold: it enables "ate" complex formation and overcomes catalytic inhibition by halide ions.
Diaklylaluminum chloride catalyzed ene reactions of aldehydes. Synthesis of ipsenol
作者:Barry B. Snider、David J. Rodini
DOI:10.1016/s0040-4039(00)92787-4
日期:1980.1
Dimethylaluminum chloride which is a mild Lewis acid and a proton scavenger, catalyzes the enereactions of aliphatic and aromatic aldehydes. Proton initiated rearrangements do not occur, since the alcohol-Lewis acid complex formed in the enereaction rapidly to give methane and a non-acidic aluminum alkoxide.
Iron-catalyzed deconstructive alkylation through chlorine radical induced C–C single bond cleavage under visible light
作者:Qiang Wu、Wei Liu、Miao Wang、Yahao Huang、Peng Hu
DOI:10.1039/d2cc03896j
日期:——
Selective C–C single bond cleavage of simple compounds is a highly challenging and desired process. Herein, a chlorine radical-induced deconstructive C–C bond alkylation with alcohols and alkenes catalyzed by iron salts was reported for the first time. Readily available alcohols and various electron-deficient alkenes were tolerated. Late-stage and large-scale reactions proceed smoothly. This catalyst