Bioinspired oxidation: The hydroxylation of alkanes with retention of the configuration and the cis‐dihydroxylation of olefins can be accomplished using [FeII(CF3SO3)2(Me,HPyTACN)] (1) as a catalyst, water as an oxygen‐atom source, and cerium ammonium nitrate (CAN) as a single‐electron oxidant. The oxidation of CH bonds and CC bonds, as well as water oxidation involves a common reaction intermediate
仿生氧化:烷烃与配置的保留和的羟基化的顺式烯烃可以使用的[Fe来实现的二羟基化II(CF 3 SO 3)2(我,H PyTACN)](1)作为催化剂,水作为氧原子源和硝酸铈铵(CAN)作为单电子氧化剂。C的氧化 H键和CC债券,以及水的氧化涉及通过CAN的反应和的[Fe形成的公共反应中间体IV(O)(OH 2)(我,H PyTACN)] +。
Synthesis of Longhorn Beetle Pheromone Components by Proline-Mediated α-Hydroxylation of Alkyl Ketones
作者:Viviana Lucía Heguaburu、Hugo do Carmo、María Eugenia Amorós、Andrés González
DOI:10.1055/a-1541-4939
日期:2021.12
The stereoselective synthesis of several components of the aggregation pheromones of numerous longhorn beetle species is described. These attractants consist of 3-hydroxy-2-alkanones and 2,3-alkyldiols with chain lengths varying from six to ten carbons. The 3R- and 3S-series are generated by organocatalytic α-hydroxylation of alkyl ketones with nitrosobenzene in the presence of l- or d-proline, respectively
amino acid-catalyzed α-oxidation of ketones with iodosobenzene and N-sulfonyloxaziridines is presented. A screen of several synthetically common oxidants revealed that iodosobenzene and N-sulfonyloxaziridines act as electrophiles in the direct organocatalytic asymmetric α-hydroxylation of ketones. The direct proline-catalyzed asymmetric α-oxidation of ketones with iodosobenzene yielded the corresponding
Enantioselective, Stereoconvergent Resolution Copolymerization of Racemic
<i>cis</i>
‐Internal Epoxides and Anhydrides
作者:Guang‐Hui He、Bai‐Hao Ren、Shi‐Yu Chen、Ye Liu、Xiao‐Bing Lu
DOI:10.1002/anie.202011259
日期:2021.3.8
unreacted epoxide at various conversions. Catalytic activity and copolymer enantioselectivity are strongly influenced by the phenolate ortho‐substituents of the ligand set, as well as the axial linker and its chirality. An enantiopure binaphthol‐linked bimetallic AlIII complex allows stereoconvergent access to the stereoregular semi‐crystalline polyesters and a concomitant kinetic resolution of the
外消旋的顺式-内部环氧化物和酸酐的前所未有的对映选择性拆分共聚反应,是由具有多个手性的双核铝配合物介导的,提供了具有两个连续立体中心的旋光聚酯,以及未反应的底物具有良好的对映选择性。在该拆分共聚中观察到了意外的立体收敛,其中共聚物的对映选择性形成的选择性因子大大超过了在各种转化率下基于未反应的环氧化物的动力学拆分系数。催化活性和共聚物的对映选择性受配体组的酚酸酯邻位取代基,轴向连接基及其手性的影响很大。对映纯联萘酚双金属Al III 配合物可以使立体收敛地接触到有规立构的半结晶聚酯,并伴随着环氧底物的动力学拆分。
Asymmetric catalytic dihydroxylation of alkenes on polymer support: Scope and limitation
作者:Braj B. Lohray、Achamma Thomas、Pabba Chittari、Jaimala R. Ahuja、Pradeep K. Dhal
DOI:10.1016/s0040-4039(00)79119-2
日期:1992.9
Osmium catalyzed asymmetricdihydroxylation of alkenes has been reported using dihydroquinidine (DHQD) and dihydroquinine (DHQ) on a polystyrene support. Effect of other oxidants and additives has been examined.