Ultrafast Iron-Catalyzed Reduction of Functionalized Ketones: Highly Enantioselective Synthesis of Halohydrines, Oxaheterocycles, and Aminoalcohols
作者:Clemens K. Blasius、Vladislav Vasilenko、Lutz H. Gade
DOI:10.1002/anie.201806196
日期:2018.8.6
A molecularly defined chiral boxmi iron alkyl complexcatalyzes the hydroboration of various functionalized ketones and provides the corresponding chiral halohydrines, oxaheterocycles (oxiranes, oxetanes, tetrahydrofurans, and dioxanes) and amino alcohols with excellent enantioselectivities (up to >99 %ee) and conversion efficiencies at low catalyst loadings (as low as 0.5 mol %). Turnover frequencies
分子定义的手性boxmi铁烷基络合物催化各种官能化酮的氢硼化,并提供相应的手性卤代醇,氧杂杂环(环氧乙烷,氧杂环丁烷,四氢呋喃和二恶烷)和氨基醇,具有出色的对映选择性(高达> 99%ee)和转化效率在低催化剂负载量(低至0.5 mol%)下。在−30°C时,周转频率大于40000 h -1突显了这种富含地球的金属催化剂的活性,该催化剂可耐受许多官能团。
Stereo- and Enantioselective Alkene Epoxidations: A Comparative Study of D4- and D2-Symmetric Homochiral trans-Dioxoruthenium(VI) Porphyrins
作者:Rui Zhang、Wing-Yiu Yu、Hong-Zhe Sun、Wei-Sheng Liu、Chi-Ming Che
dioxoruthenium(VI) porphyrins proceeds through the rate-limiting formation of a benzylic radical intermediate; the observed enantioselectivity (eeobs) depends on both the facial selectivity of the first C-O bond formation step and the diastereoselectivity of the subsequent epoxide ring closure. To account for the observed facial selection, "side-on" and "top-on" approach transition state models are examined
tetra-substituted aromatic olefins with versatile functional groups can be epoxidized with this type of catalyst in good to excellent yields (up to 100 %) with moderate to good enantioselectivies (up to 84 % ee). Additive and solvent effects as well as the relative rate of reaction with different catalysts have been established. It is shown that the presence of weak organic acids or an electron-withdrawing
Enantioselective water-soluble iron–porphyrin-catalyzed epoxidation with aqueous hydrogen peroxide and hydroxylation with iodobenzene diacetate
作者:Paul Le Maux、Hassan F. Srour、Gérard Simonneaux
DOI:10.1016/j.tet.2012.05.014
日期:2012.7
The asymmetric epoxidation of styrene derivatives by H2O2 (or UHP) to give optically active epoxides (ee up to 81%) and hydroxylation of alkanes to give optically active secondary alcohols (ee up to 78%) were carried out in methanol and water using chiral water-soluble ironporphyrins as catalysts.
H 2 O 2(或UHP)对苯乙烯衍生物进行不对称环氧化,得到旋光性环氧化物(ee高达81%),烷烃的羟基化反应得到旋光性仲醇(ee高达78%)在甲醇中进行。使用手性水溶性铁卟啉作为催化剂的水。
Nitration of Halterman porphyrin: a new route for fine tuning chiral iron and manganese porphyrins with application in epoxidation and hydroxylation reactions using hydrogen peroxide as oxidant
作者:Nesrine Amiri、Paul Le Maux、Hassan Srour、Habib Nasri、Gérard Simonneaux
DOI:10.1016/j.tet.2014.10.001
日期:2014.11
regioselective nitration of the phenyl groups of Halterman porphyrin, using NaNO2. These nitro-porphyrins can be reduced to aminoporphyrins and then N-dimethylated to give new optically active porphyrins. Applications to the asymmetric epoxidation of styrene derivatives by H2O2 to give optically active epoxides (ee up to 60%) and hydroxylation of alkanes to give optically active secondary alcohols (ee up to
报道了使用NaNO 2进行Halterman卟啉的苯基的区域选择性硝化的方法。可以将这些硝基卟啉还原为氨基卟啉,然后进行N-二甲基化以生成新的旋光卟啉。在有机溶剂(二氯甲烷)中应用H 2 O 2进行苯乙烯衍生物的不对称环氧化,得到旋光性环氧化物(ee最高60%),烷烃的羟基化得到旋光性仲醇(ee最高69%)。 /甲醇),使用手性铁和锰卟啉作为催化剂。