Asymmetric Chlorination/Ring Expansion for the Synthesis of α-Quaternary Cycloalkanones
作者:Qin Yin、Shu-Li You
DOI:10.1021/ol5005565
日期:2014.3.21
A highly enantioselective chlorination/ringexpansion cascade for the construction of cycloalkanones with an all-carbon quaternary center was realized (up to 97% ee). Oxa-cyclobutanol substrates were employed for the first time in the ringexpansionreactions, affording the functionalized dihydrofuranones in excellent enantioselectivity.
Synthesis of Unsymmetrical 1,4-Dicarbonyl Compounds by Photocatalytic Oxidative Radical Additions
作者:Ya Dong、Ruining Li、Junliang Zhou、Zhankui Sun
DOI:10.1021/acs.orglett.1c02208
日期:2021.8.20
Herein we report a photocatalytic oxidative radical addition reaction for the synthesis of unsymmetrical 1,4-dicarbonyl compounds. This reaction utilizes a desulfurization process to generate electrophilic radicals, which add to α-halogenated alkenes and undergo further oxidation to deliver 1,4-dicarbonyl compounds. This mild and highly efficient method provides a valuable alternative to known strategies
reaction in the chemical industry. A large proportion of SM couplings employ dipolaraproticsolvents; however, current sustainability initiatives and increasingly stringent regulations advocate the use of alternatives that exhibit more desirable properties. Here we describe the scope and utility of the bio-derived solvent Cyrene™ in SM cross-couplings and evaluate its suitability as a reaction medium
Suzuki-Miyaura (SM) 交叉偶联是化学工业中使用最广泛的 Pd 催化的 C-C 键形成反应。大部分 SM 偶联剂使用偶极非质子溶剂;然而,当前的可持续性举措和日益严格的法规提倡使用具有更理想特性的替代品。在这里,我们描述了生物衍生溶剂 Cyrene™ 在 SM 交叉偶联中的范围和效用,并评估其作为反应介质的适用性,以实现从发现到克级规模的这一基准转化。
A Cascade Suzuki–Miyaura/Diels–Alder Protocol: Exploring the Bifunctional Utility of Vinyl Bpin
Cascade reactions are an important strategy in reaction design, allowing streamlining of chemical synthesis. Here we report a cascade Suzuki–Miyaura/Diels–Alder reaction, employing vinyl Bpin as a bifunctional reagent in two distinct roles: as an organoboron nucleophile for cross-coupling and as a Diels–Alder dienophile. Merging these two reactionsenables a rapid and operationally simple synthesis
Rhodium(III)-Catalyzed Cyclopropanation of Unactivated Olefins Initiated by C–H Activation
作者:Erik J. T. Phipps、Tiffany Piou、Tomislav Rovis
DOI:10.1055/s-0039-1690130
日期:2019.9
We have developed a Rh(III)-catalyzed cyclopropanation of unactivated olefins initiated by an alkenyl C-H activation. A variety of 1,1-disubstituted olefins undergo efficient cyclopropanation with a slight excess of alkene stoichiometry. A series of mechanistic interrogations implicate a metal-carbene as an intermediate.