Preparation and Control of Coordinatively Unsaturated Active Species

以dppe、dppp、dpppb、diop、dppf、binap等不同的膦为原料制备了5个配位钌配合物[RuH(P-P)_2]PF_6，其中dppe为1,2-二（二苯基膦）乙烷，dppp为1,3-二（二苯基膦）丙烷，dppb为1,4-二（二苯基膦）丙烷，dop为2,3-o-异丙基-2,3-二羟基-1,4-二（二苯基膦）丁烷，dppf为1,2-二（二苯基膦）二茂铁，binap为2,2'-二（二苯基膦）-1,1'-二萘。这些配合物的核磁共振研究表明，它们在溶液中具有溶剂、氮分子等第六配体。当配合物与磷化氢具有大的螯合环时，观察到主要形成顺式异构体，并与磷化氢的苯基相互作用。对dppb在氩气、氮气和氢气气氛下的进一步研究表明，这种相互作用强于氮分子或溶剂的配位作用，弱于氢分子的配位作用。通过x射线分析确定了dppf配合物的结构，表明dppf的位阻作用使其呈顺式结构。氢分子与该配合物配位，得到新型分子型氢配合物。该配合物的H_2配体T_1值表明H_2与原氢化物配体相等，即为三氢化物配合物。在锆的情况下，我们发现了以下几点。锆新烯二烷基定量生成的活性物质为锆新烯（II）烯烃配合物。用x射线分析确定了锆茂烯配合物的结构。锆新统烯烃配合物与其它烯烃反应得到具有>99%区域选择性和>99%立体选择性的烯烃-烯烃交叉偶联产物。此外，对其机理的详细研究导致了氧化锆或半环戊烷衍生物中碳碳键活化的新型骨架重排的发展。该方法可选择性地将α位甲基转移到β位。少

Five coordinate ruthenium complexes [RuH(P-P)_2]PF_6 were prepared with various phosphines such as dppe, dppp, dpppb,diop, dppf, binap, where dppe is 1,2-bis(diphenylphosphino)ethane, dppp is 1,3-bis(diphenylphosphino)propane, dppb is 1,4-bis(diphenylphosphino)-propane, diop is 2,3-o-isopropylidene-2,3-dihydroxy-1,4-bis(diphenylphosphino)butane, dppf is 1,2-bis(diphenylphosphino)ferrocene, binap is 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl. The NMR studies of these complexes indicated that they have a 6th ligand such as solvent, nitrogen molecule and so on, in solution. When complexes have large chelate rings with phosphines, observed were predominant formation of cis isomers with agostic interactions with phenyl group of phosphines. Further investigations with dppb under argon, nitrogen or hydrogen atmosphere revealed that this agostic interaction was stronger than the coordination of nitrogen molecule or solvent, and weaker than molecular hydrogen coordination. The structure of dpp … More f-complex was determined by x-ray study, indicating the cis-structure due to the steric hindrance of dppf. Hydrogen molecule coordinated to this complex to give novel type of molecular hydrogen complex. T_1 value of H_2 ligand of this complex showed that the H_2 and original hydride ligands are equivalent, in other word, this was a trihydride complex.In the case of zirconium species, we found the followings. The active species quantitatively formed from zirconocenedialkyls were zirconocene(II) olefin complexes. The structure of zirconocenestilbene complex was determined by x-ray analysis. Reactions of zirconocene olefin complexes with another olefins gave olefin-olefin cross coupling products with >99% of regio-selectivities and >99% of stereo-selectivities. In addition the detail investigations of its mechanism led the development: of novel skeleton rearrangement by carbon-carbon bond activation in the case of zircona- or hafnacyclopentane derivatives. Methyl group of alpha-position could be transferred to beta-position selectively by this novel method. Less