Division of Chemistry and Biological Chemistry, School of Physical & Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.
Dalton Trans. 2012 May 7;41(17):5391-400. doi: 10.1039/c2dt12379g.
A series of enantiomerically pure 1,2-diester substituted P,N-ligands incorporating two chiral carbons in the backbone were generated in high yields and high stereoselectivity from acetylenedicarboxylate via initial hydrophosphination using diphenylphosphine followed by hydroamination with various primary and secondary amines. The reactions were activated and stereochemically controlled by the organopalladium complex containing ortho-palladated (S)-(1-(dimethylamino)ethyl)naphthalene under mild conditions. The absolute stereochemistry and the coordination chemistry of P,N-products were determined by the single crystal X-ray diffraction analysis. All the chiral P,N-ligands could be liberated from the palladium template without loss of optical purity. Subsequent recomplexation to selected chiral palladium centers confirmed the optical purity of the new functionalized chiral P,N-ligands.
一系列对映体纯的 1,2-二酯取代的 P,N-配体，在温和条件下，通过初始膦氢化反应使用二苯基膦，然后与各种伯胺和仲胺进行氢氨化反应，从乙炔二羧酸酯高产率和高立体选择性地生成，在骨架中包含两个手性碳原子。这些反应由含有邻位钯化（S）-（1-（二甲基氨基）乙基）萘的有机钯配合物激活并具有立体化学控制。P,N-产物的绝对立体化学和配位化学通过单晶 X 射线衍射分析确定。所有手性 P,N-配体都可以从钯模板中释放出来，而不会损失光学纯度。随后与选定的手性钯中心重新络合，证实了新功能化手性 P,N-配体的光学纯度。
