Preparation of Chiral Allenes through Pd-Catalyzed Intermolecular Hydroamination of Conjugated Enynes: Enantioselective Synthesis Enabled by Catalyst Design
作者:Nathan J. Adamson、Haleh Jeddi、Steven J. Malcolmson
DOI:10.1021/jacs.9b02637
日期:2019.5.29
surrogate to afford primary amines in a two-step/one-pot process. Examination of chiral catalysts revealed a high degree of reversibility in the C-N bond formation that negatively impacted enantioselectivity. Consequently, an electron-poor ferrocenyl-PHOX ligand was developed to enable efficient and enantioselective enyne hydroamination.
A radical-mediated 1,3,4-trifunctionalization cascade of 1,3-enynes with sulfinates and <i>tert</i>-butyl nitrite: facile access to sulfonyl isoxazoles
作者:Xin Yue、Ming Hu、Xingyi He、Shuang Wu、Jin-Heng Li
DOI:10.1039/d0cc01659d
日期:——
indium-promoted three-component 1,3,4-trifunctionalization cascade of 1,3-enynes with sodium sulfinates and tert-butyl nitrite (TBN) to access 5-sulfonylisoxazoles via [3+2] annulation is reported. By employing TBN as both the radical initiator and the N–O two atom unit, this method enables the formation of three new carbon–heteroatom bonds, C–S, C–N and C–Obonds, in a single reactionthrough a sequence
Switch in Selectivity for Formal Hydroalkylation of 1,3‐Dienes and Enynes with Simple Hydrazones
作者:Leiyang Lv、Lin Yu、Zihang Qiu、Chao‐Jun Li
DOI:10.1002/anie.201915875
日期:2020.4.16
anti-Markovnikov addition is obtained by changing to a ruthenium catalyst, thus providing direct and efficient access to homoallylic products exclusively. Isotopic substitution experiments indicate that no reversible hydro-metallation across the metal-π-allyl system occurred under ruthenium catalysis. Moreover, this protocol is applicable to the regiospecific hydroalkylation of the distal C=C bond of 1,3-enynes
(2-bromoethyl)diphenylsulfonium triflate to be a powerful vinylation reagent was determined by the Sonogashira cross-coupling reactions with terminal alkynes. The vinylation proceeded smoothly at 25 °C under Pd/Cu catalysis to afford a variety of 1- and 2-unsubstituted 1,3-enynes in moderate to excellent yields. This protocol represents the first application of (2-haloethyl)diphenylsulfonium triflate as a CH═CH2 transfer
Asymmetric Construction of Fluoroalkyl Tertiary Alcohols through a Three-Component Reaction of (Bpin)<sub>2</sub>, 1,3-Enynes, and Fluoroalkyl Ketones Catalyzed by a Copper(I) Complex
作者:Xu-Cheng Gan、Qi Zhang、Xue-Shun Jia、Liang Yin
DOI:10.1021/acs.orglett.7b04039
日期:2018.2.16
An asymmetric three-component reaction of Bis(pinacolato)diboron ((BPin)2), 1,3-enynes, and fluoroalkyl ketones was carried out by using a copper(I)-Ph-BPE complex as the catalyst, which afforded a series of chiral fluoroalkyl diols in good to high yield, good to high diastereoselectivity, and high enantioselectivity after an oxidative workup. The reaction exhibits advantages that include a broad substrate