Optically active diphenylphosphino-binaphtyl compounds and catalytic transition metal complexes thereof
申请人:Takasago International Corporation
公开号:EP0503884A1
公开(公告)日:1992-09-16
A phosphine compound is represented by the formula:
wherein Ph represents a -C₆H₅ or -C₆F₅ group; and R represents a lower alkyl group, e.g. C1-4, or -OR¹ where R¹ represents a hydrogen atom, a C5-C7 cycloalkyl group or a C1-6 (e.g. Cl-4) alkyl group which may be substituted with a halogen atom, a lower alkoxy group-substituted lower alkxoy group, or a phenyl group.
The complexes are synthesised from binaphthol (II) which is converted in turn with diphenylphosphine oxide; and then (a) NaOH, HCl and a reducing or alkylating agent; or (b) an alkyl magnesium halide and a reducing agent.
The optical activity such as (+)- or (-)- or racemate thereof depends on the activity of the (II).
A compound of a transition metal, e.g. Pd, is reacted with (I) to form a complex which is used as a catalyst for various enantioselective synthesis reactions, e.g., enantioselective silylation reaction, and provides a desired product in high yield at high optical purity. The absolute configuration of the product can be selected by selecting the optical isomer of the ligand in the complex catalyst.
膦化合物用式表示:
其中 Ph 代表-C₆H₅或-C₆F₅基团;R 代表低级烷基,如 C1-4,或-OR¹,其中 R¹ 代表氢原子、C5-C7 环烷基或 C1-6(如 Cl-4)烷基,可被卤素原子、低级烷氧基取代的低级烷氧基或苯基取代。
配合物是由二萘酚 (II) 合成的,二萘酚 (II) 与二苯基氧化膦依次转化,然后 (a) NaOH、HCl 和还原剂或烷基化剂;或 (b) 烷基卤化镁和还原剂。
光学活性如 (+)- 或 (-)- 或其外消旋物取决于 (II) 的活性。
过渡金属(如钯)的化合物与(I)反应生成一种配合物,该配合物可用作各种对映选择性合成反应(如对映选择性硅烷化反应)的催化剂,并能以高产率和高光学纯度提供所需的产物。通过选择络合物催化剂中配体的光学异构体,可以选择产物的绝对构型。