A novel, highly modular approach has been developed for the synthesis of new chiral P,N,N ligands with the general formula Ph₂P(CH₃)CH(CH₂)_mCH(CH₃)NHCH₂CH₂(CH₂)_nN(CH₃)₂ and Ph₂P(CH₃)CHCH₂CH(CH₃)NHCH₂(CH₂)_n-2-Py (m, n = 0, 1). The systematic variation of their PN and NN backbone led to the conclusion that the activity, chemo- and enantioselectivity in the hydrogenation of α,β-unsaturated ketones are highly dependent on the combination of the two bridge lengths. It has been found that a minor change in the ligand's structure, i. e. varying the value of m from 1 to 0, can switch the chemoselectivity of the reaction, from 80% CO to 97% CC selectivity.

已开发出一种新颖的，高度模块化的方法，用于合成通式为Ph ₂ P（CH ₃）CH（CH ₂）_m CH（CH ₃）NHCH ₂ CH ₂（CH ₂）的新手性P，N，N配体）_n N（CH ₃）₂和Ph ₂ P（CH ₃）CHCH ₂ CH（CH ₃）NHCH ₂（CH ₂）_n -2-Py（m，n  = 0，1）。它们的PN和N的系统变化N主链得出的结论是，α，β-不饱和酮氢化中的活性，化学选择性和对映选择性高度依赖于两个桥长度的组合。已经发现，配体结构的微小变化，即将m的值从1改变为0，可以将反应的化学选择性从80％CO转化为97％CC。