Ruck Rebecca T, Jacobsen Eric N
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.
J Am Chem Soc. 2002 Mar 27;124(12):2882-3. doi: 10.1021/ja025588j.
Tridentate Schiff base chromium(III) complex 1 catalyzes the asymmetric hetero-ene reaction between aryl aldehydes and either 2-methoxypropene or 2-trimethylsilyloxypropene to provide a series of beta-hydroxyenol ether products in high yields and enantioselectivities. X-ray crystallographic analysis of a closely related chromium complex reveals a bridged, dimeric structure bearing aquo-bound six-coordinate Cr(III) centers. A mechanism is proposed wherein water dissociation is effected by means of a chemical desiccant (BaO or silyl enol ether), thereby revealing the site for aldehyde complexation.
三齿席夫碱铬（III）配合物1催化芳醛与2-甲氧基丙烯或2-三甲基硅氧基丙烯之间的不对称杂环烯反应，以高收率和对映选择性提供一系列β-羟基烯醚产物。对一种密切相关的铬配合物的X射线晶体学分析揭示了一种具有水合配位的六配位Cr（III）中心的桥连二聚体结构。提出了一种机理，其中水的解离通过化学干燥剂（BaO或硅烯醇醚）实现，从而揭示醛络合的位点。
