Provided is a process for the preparation of asymmetrically substituted biaryldiphosphine ligands of the formula, (I) wherein R1 is C1-6-alkyl or C3-10-cycloalkyl optionally substituted with one or more halogen atoms, and R2 and R3 are equal and are C5-10-cycloalkyl or C1-6-alkyl, or R2 is C5-10-cycloalkyl or C1-6-alkyl, and R3 is aryl optionally substituted with one or more substituents selected from the group consisting of halogen atoms, nitro, amino, C1-6-alkyl, C1-6-alkoxy and di-C1-6-alkylamino groups, and each C1-6-alkyl, C1-6-alkoxy, di-C1-6-alkylamino and C5-10-cycloalkyl group in R2 and R3 optionally being substituted with one or more halogen atoms, from 2,2’, 6, 6’-tetra-bromobiphenyl by a sequence of bromine-metal exchanges and subsequent reactions.
提供了一种制备不对称取代的双芳基二
膦配体的过程,其
化学式为(I),其中R1是C1-6-烷基或C3-10-环烷基,可选择性地取代一个或多个卤原子;R2和R3相等,均为C5-10-环烷基或C1-6-烷基;或者R2是C5-10-环烷基或C1-6-烷基,R3是芳基,可选择性地取代一个或多个取代基,所述取代基选自卤原子、硝基、
氨基、C1-6-烷基、C1-6-烷氧基和二C1-6-烷基
氨基团;R2和R3中的每个C1-6-烷基、C1-6-烷氧基、二C1-6-烷基
氨基和C5-10-环烷基团可选择性地取代一个或多个卤原子,该过程通过
溴金属交换和随后的反应从2,2',6,6'-
四溴联苯进行。