The Aerobic Oxidation and C=C Bond Cleavage of Styrenes Catalyzed by Cerium(IV) Ammonium Nitrate (CAN)
作者:Lei Yu、Yaping Huang、Zengbing Bai、Bingchun Zhu、Kehong Ding、Tian Chen、Yuanhua Ding、Yuguang Wang
DOI:10.1002/jccs.201400421
日期:2015.6
The CAN‐catalyzed aerobic oxidation severed the C=C bond selectively through the single electron transfer mechanism, giving a green method to decompose olefins. Compared with the literature reported examples, this method required simple catalyst, cheap, abundant and clean oxidant and was very safe to operate due to the mild conditions.
1,3-Dibromo-5,5-dimethylhydantoin (DBH) mediated one-pot syntheses of α-bromo/amino ketones from alkenes in water
作者:Senhan Xu、Ping Wu、Wei Zhang
DOI:10.1039/c6ob02200f
日期:——
a relatively hazardous/complex reagent combination, a long reaction time, the use of non-environmentally friendly solvents, or a limited substrate scope. Herein, we describe the development of a new methodology for the preparation of α-bromo ketones from alkenes using 1,3-dibromo-5,5-dimethylhydantoin (DBH) as a bromine source and an oxidant simultaneously. This easy to carry out two-step one-pot protocol
A highly efficient and selective rearrangement reaction of bromohydrins to aldehydes mediated by CF3CO2ZnEt was described. The secondary and tertiary aldehydes were prepared under mild conditions in good to excellent yields (85–99%). The scope and limitations of this rearrangement process were also investigated.
描述了由CF 3 CO 2 ZnEt介导的溴代醇对醛类的高效选择性重排反应。仲醛和叔醛是在温和的条件下以良好至极佳的收率(85–99%)制备的。还研究了这种重排过程的范围和局限性。
Furanoside phosphite–phosphoroamidite and diphosphoroamidite ligands applied to asymmetric Cu-catalyzed allylic substitution reactions
A phosphite–phosphoroamidite and diphosphoroamidite ligand library was applied in the Cu-catalyzedallylicsubstitution of a range of cinnamyl-type substrates using several organometallic nucleophiles. Results indicated that selectivity depended strongly on the ligand parameters (position of the phosphoroamidite group at either C-5 or C-3 of the furanoside backbone, as well as the configuration of
Improvements and Applications of the Transition Metal-Free Asymmetric Allylic Alkylation using Grignard Reagents and Magnesium Alanates
作者:David Grassi、Alexandre Alexakis
DOI:10.1002/adsc.201500495
日期:2015.10.12
Two new N-heterocyclic carbene (NHC) ligands have been synthesized and employed in the transition metal-free asymmetric allylic alkylation (AAA) mediated by Grignardreagents and magnesium alanates. The employment of these ligands showed high yields and improved regio- and enantioselectivity in the formation of tertiary and quaternary stereocenters. Moreover, the low catalyst loading (up to 0.3 mol%)