[{W(O)(O
<sub>2</sub>
)
<sub>2</sub>
(H
<sub>2</sub>
O)}
<sub>2</sub>
(μ‐O)]
<sup>2–</sup>
‐Catalyzed Epoxidation of Allylic Alcohols in Water with High Selectivity and Utilization of Hydrogen Peroxide
A dinuclear peroxotungstate, K2[W(O)(O2)2(H2O)}2(μ-O)]⋅2 H2O, exhibits high catalytic performance for the epoxidation of various allylic alcohols with only one equivalent of hydrogen peroxide at 305 K in water solvent. The effectiveness of this system is evidenced by high chemo-, regio-, and diastereoselectivity, and stereospecificity for the epoxidation of allylic alcohols. Furthermore, products/catalyst
Regio- and Diastereoselective Catalytic Epoxidation of Acyclic Allylic Alcohols with Methyltrioxorhenium: A Mechanistic Comparison with Metal (Peroxy and Peroxo Complexes) and Nonmetal (Peracids and Dioxirane) Oxidants
作者:Waldemar Adam、Catherine M. Mitchell、Chantu R. Saha-Möller
DOI:10.1021/jo9902289
日期:1999.5.1
Geraniol and its 1-methyl derivative (regiochemical probes) and a set of methyl- and tert-butyl-substituted chiral allylicalcohols (stereochemical probes) have been used to elucidate the mechanism of the MTO-catalyzed epoxidation of allylicalcohols. The regiochemical probes are preferentially epoxidized at the unfunctionalized double bond by these MTO-based oxidants, which establishes that MTO/UHP
Effect of Additives on Chemoselectivity and Diastereoselectivity in the Catalytic Epoxidation of Chiral Allylic Alcohols with Hydrogen Peroxide and Binuclear Manganese Complexes
作者:Hamdullah Kilic、Waldemar Adam、Paul L. Alsters
DOI:10.1021/jo801974e
日期:2009.2.6
chiral allylicalcohols 2 by manganese complexes of the cyclic triamine 1,4,7-trimethyl-1,4,7-triazacyclononane (tmtacn) 1 and hydrogen peroxide as oxygen donor in the presence of co-catalyst are investigated to understand the factors that affect the catalyst selectivity. Chemoselectivity and diastereoselectivity of catalyst 1 are significantly affected by the structure of the allylicalcohol and the
研究了在助催化剂存在下,环状三胺1,4,7-三甲基-1,4,7-三氮杂环壬烷(tmtacn)1和过氧化氢作为氧供体的锰配合物对手性烯丙基醇2的催化氧化,了解影响催化剂选择性的因素。烯丙醇的结构以及助催化剂的性质和量显着影响催化剂1的化学选择性和非对映选择性。H 2 O 2的添加摩尔当量(相对于基材为20-110 mol%)的影响更为明显。我们目前的结果反映了Mn催化剂1 / H 2的复杂氧化还原化学反应O 2 /助催化剂体系在烯烃氧化的早期阶段。
The diastereoselective epoxidation of olefins in supercritical carbon dioxide
作者:Geoffrey R Haas、Joseph W Kolis
DOI:10.1016/s0040-4039(98)01212-x
日期:1998.8
CO2. The metal catalyst was prepared in a simple two step, Schiff base reaction to form the salen ligand, followed by complexation to the vanadyl group. The epoxidation reactions are clean and give both high yields and good diastereoselectivity.
A convenient, highly stereoselective synthesis of anti-α,β-epoxy alcohols by the Luche reduction of α,β-epoxy ketones
作者:Keqiang Li、Lawrence G. Hamann、Masato Koreeda
DOI:10.1016/s0040-4039(00)60987-5
日期:1992.10
Reduction of α,β-epoxyketones under the Luche conditions with NaBH4/CeCl3 in MeOH provides anti- (or erythro-) α,β-epoxyalcohols in high yields and with extremely high stereoselectivity.