通过[Ru {(S)-phgly} 2 {(S)-binap}]和C 6 H 5 OLi的联合体系催化,HCN向α,β-不饱和酮的对映选择性共轭加成反应提供了高浓度的β-氰基酮产量(请参阅计划)。没有产生可检测量的相应的1,2-加合物,叔C 4 H 9 OCH 3是选择的溶剂。在-20-0°C下,氰化反应以底物与催化剂的摩尔比在200:1-1000:1的范围内进行。
aerobic oxidative cyclization of β,γ-unsaturated hydrazones for the preparation of pyrazole derivatives has been developed. The hydrazonyl radical promoted the cyclization, along with a concomitant C═Cbondcleavage of β,γ-unsaturated hydrazones. This process has been verified via several control experiments, including a radical-trapping study, an 18O-labeling method, and the identification of the possible
Copper-Catalyzed Asymmetric Cyanation of Alkenes via Carbonyl-Assisted Coupling of Alkyl-Substituted Carbon-Centered Radicals
作者:Song Zhou、Guoyu Zhang、Liang Fu、Pinhong Chen、Yibiao Li、Guosheng Liu
DOI:10.1021/acs.orglett.0c02085
日期:2020.8.21
the first copper-catalyzed asymmetric cyanation of alkyl-substituted alkenes has been developed. The reaction, featuring mild reaction conditions and excellent functional group compatibilities, provides an easy access to a wide array of structurally diverse enantioenriched alkyl nitriles in good yields. Notably, an unstable carbon-centered radical generated by trifluoromethyl radical addition across terminal
A novel and efficient strategy for the synthesis of 1,6-dihydropyridazines via copper-promoted 6-endo-trig cyclization of readily available β,γ-unsaturated hydrazones have been developed. A series of 1,6-dihydropyridazines have been synthesized by this method with good yields, high functional group tolerance, and remarkable regioselectivity under mild conditions. Importantly, the 1,6-dihydropyridazines