我们报道了新型手性三齿[NO 2 ] H 2和四齿[N 2 O 2 ] H 2包含平面手性二茂铁部分的席夫碱配体与具有中心或轴向手性的羟基亚胺或二亚胺供体连接。从结构上讲,这些配体类似于为它们的过渡金属配合物在均相催化中的立体选择性应用而设计的salen-salen和salen体系。模块化合成包括手性二茂铁或五甲基二茂铁乙缩醛的非对映选择性金属化,然后分别进行立体保守的羟烷基化和与手性羟胺或二胺的缩合。与Salen型系统相比,这些配体的重要优点是它们对醇盐供体位点的可调节的空间保护。总共制备了18种不同的电子和空间性质的配体,并通过NMR,IR,
Preparation of planar chiral ferrocenes containing a fluorous alcohol function
作者:Victoria Albrow、Alexander J. Blake、Alexandre Chapron、Claire Wilson、Simon Woodward
DOI:10.1016/j.ica.2005.05.040
日期:2006.4
Ferrocene reacts with hexafluoroacetone trihydrate in refluxing octane to afford > 80% yields of [CpFe(eta(5)-C5H4C(CF3)(2)OH)] (X-ray), carrying out the reactions at 180 degrees C gives an additional 5% yield of [Fe(eta(5)-C5H4C(CF3)(2)OH)(2)] (X-ray). The mono alcohol is lithiated with Bu'OK/Bu"Li/TMEDA affording partial conversion to mixtures of [CpFe(1,2-eta(5)-C5H3C(CF3)(2)OH)(X)] and [Fe(eta(5)-C5H4X)(1,2-eta(5)- C5H3C(CF3)(2)OH)(X)] (X = SMe, CPh2OH) upon reaction with Me2S2 or O=CPh2. For X = CPh2OH both structures are crystallographically characterised. Enantiopure [CpFe(1,2-eta(5)-C5H3C(CF3)(2)OH)(SMe)] can be prepared from (R)-[CpFe(eta(5)-C5H4S(O)C6H4Me)] via [CpFe(1,2-eta(5)-C5H3S(O)C6H4Me)(C(CF3)(2)OH)] (X-ray) or [CpFe(1,2-eta(5)-C5H3S(O)C6H4Me)(SMe)]. Related procedures allow the preparation of [CpFe(1,2-eta(5)-C5H3CPh2OH)(Y)] (Y = SMe, CHO (X-ray), C(CF3)(2)OH) and (CpFe(1,2-eta(5)-C5H3C(CF3)(2)OH)(CHO)]. (c) 2005 Elsevier B.V. All rights reserved.