Design, synthesis and application of new ligands play a central role in the development of homogeneous catalysis. Among vast varieties, phosphine ligands find not only attractions in organometallic chemistry but also wide applications in processes of both industrial and laboratory scales.Choosing triphenylphosphine as structural model, two strategies in ligand design were tried out. In the backbone of triphenylphosphine secondary functionalities such as polyether chain and pyrazolylpyridine were introduced through an imine linker. The secondary interactions between the functionalized phosphines and the Lewis acids are not only detectable by means of 31P NMR spectroscopy but are of relevance for catalysis.The second route to functionalized phosphines was realized by the introduction of pyrazole and pyrimidine (eventually also NHC-) groups into triphenylphosphine. Thus obtained hemilabile P,N- bidentate ligands showed the best catalytic activity in the C-C coupling reactions. The further incorporation of substituents with different electronic and steric properties would allow the fine-tuning of the resulting complexes and their applications in homogeneous catalysis.
Dr. Yu SUN was born in Chongqing. After studies at East China University of Science and Technology (1989-1993) and at Dalian University of Technology (1993-1996) he received his Ph.D. in chemistry in 1999 with Prof. Zuwei XI from Dalian Institute of Chemical Physics, Chinese Academy of Sciences. In 2000 he went to University of Paris V as a postdoctoral fellow with Prof. Daniel MANSUY. After that he joined the group of Prof. Dr. Werner R. THIEL at Chemnitz University of Technology in 2001. In 2006 he was appointed the head of the X-ray Diffraction Laboratory in Department of Chemistry at Kaiserslautern University of Technology. He is currently a senior lecturer there. His research interests include X-ray structure analysis, inter-/intra- molecular weak interactions (in the solid state), and homogeneous catalysis, especially ligand design and process development.