Oxime Radical Promoted Dioxygenation, Oxyamination, and Diamination of Alkenes: Synthesis of Isoxazolines and Cyclic Nitrones
作者:Bing Han、Xiu-Long Yang、Ran Fang、Wei Yu、Chao Wang、Xiao-Yong Duan、Shuai Liu
DOI:10.1002/anie.201203799
日期:2012.8.27
Up the tempo: The intramolecular addition of oxime radicals to CC bonds was achieved by using DEAD and TEMPO to give 4,5‐dihydroisoxazoles as a result of a CO bond‐forming, 5‐exo‐trig cyclization. γ,δ‐Unsaturated ketoximes also reacted to afford cyclicnitrones through CN bond formation. The reactions offer a metal‐free approach for the vicinal difunctionalization of unactivated alkenes.
d domino hydrosilylation of substrates carrying unsaturated functionalities in a proximal arrangement is presented to produce silacycles. Excellent levels of efficiency and selectivity were achieved in the cyclization by the deliberate choice of the hydrosilane reagents. The key to successful cyclic hydrosilylation is the reactivity enhancement of the second intramolecular hydrosilylation by a proximity
Ketone Formation via Mild Nickel-Catalyzed Reductive Coupling of Alkyl Halides with Aryl Acid Chlorides
作者:Fan Wu、Wenbin Lu、Qun Qian、Qinghua Ren、Hegui Gong
DOI:10.1021/ol3011198
日期:2012.6.15
The present work highlights unprecedented Ni-catalyzed reductive coupling of unactivated alkyl iodides with aryl acid chlorides to efficiently generate alkyl arylketones under mild conditions.
Organometallic-type reactions in aqueous media mediated by indium. Allylation of acyloyl-imidazoles and pyrazoles. Regioselective synthesis of β,γ-unsaturated ketones
作者:Vernal J. Bryan、Tak-Hang Chan
DOI:10.1016/s0040-4039(97)01512-8
日期:1997.9
Indiummediated coupling of allylic bromide with acyloyl-imidazoles or pyrazoles in aqueousmedia gives the corresponding tertiary alcohols or ketones in good yield. The reaction provides a facile regioselective synthesis of β,γ-unsaturated ketones and its usefulness is demonstrated by the synthesis of the monoterpene artemesia ketone.
highly efficient Pd/Xiang-Phos catalyzedenantioselective carboetherification of alkenyl oximes with either aryl or alkenyl halides, delivering various chiral 3,5-disubstituted and 3,5,5-trisubstituted isoxazolines in good yields with up to 97 % ee. The sterically bulky and electron-rich (S,Rs)-NMe-X2 ligand is responsible for the excellent reactivities and enantioselectivities. The salient features of this