Biscyclopentadienyl, Group 4 transition metal complexes containing a conjugated diene ligand group wherein the diene is bound to the transition metal either in the form of o-complex or a T-complex are readily prepared by reacting in any order: a) a Group 4 metal salt corresponding to the formula MX or M"X, or a Lewis base adduct thereof, b) a conjugated diene, D', c) a reducing agent, and d) a compound of the formula: CpM* or (Cp–Cp)Mn. wherein. M" is titanium, zirconium or hafnium in the +3 formal oxidation state; M" is titanium, zirconium or hafnium in the +4 formal oxidation state; Xis a halide, Chydrocarbyloxy or di(C. hydrocarbyl) amido group; D' is an uncoordinated diene having the same number of carbons as D and the same substitution pattern as D; M* is a Group 1 or 2 metal cation, a Grignard reagent cation or a tri(C. hydrocarbyl)silyl group; and n is 1 when M* is a Group 2 metal cation and n is 2 when M" is a Group 1 metal cation, a Grignard reagent cation, or a trihydrocarbylsilyl group with the proviso that reagents a), and d) are not contacted with one another in the absence of reagent c).

La presente invention concerne un procede de synthese d'une composition a tetes multiples ou a deux tetes a l'aide d'un compose alpha, omega-diene et d'un compose organometallique en presence d'un precurseur de catalyseur. L'utilisation des compositions dans la polymerisation d'olefines, ainsi que leur procede de production sont en outre decrits.

Agnew. Chem. Int. Ed. Engl., "(n-Allyl)(n-butadiene)(n-cyclopentadienyl)-Zirconium, a System of Isomeric Monocyclopentadienylzirconium (II) Compounds' Erker et al., 1984, vol. 23, pp. 455-456. Organometallics, "Structural Features in Electron-Deficient (n-Pentamethylcyclopentadienyl) titanium-Diene Com plexes and Their Catalysis in the Selective Oligomerization of Conjugated Dienes' Yamamoto, et al., 1989, 8, pp. 105-119.

Organic light-emitting diode (OLED) displays have been an active and intense area of research for well over a decade and have now reached commercial success for displays from cell phones to large format televisions. A more thorough understanding of the many different potential degradation modes which cause OLED device failure will be necessary to develop the next generation of OLED materials, improve device lifetime, and to ultimately improve the cost vs performance ratio. Each of the different organic layers in an OLED device can be susceptible to unique decomposition pathways, however stability toward excitons is critical for emissive layer (EML) materials as well as any layer near the recombination zone. This study will specifically focus on degradation modes within the hole transport layer (HTL) with the goal being to identify the general decomposition paths occurring in an operating device and use this information to design new derivatives which can block these pathways. Through post-mortem analyses of several aged OLED devices, an apparently common intramolecular cyclization pathway has been identified that was not previously reported for arylamine-containing HTL materials and that operates parallel to but faster than the previously described fragmentation pathways.

Solid-state solvation (SSS) is a solid-state analogue of solvent solute interactions in the liquid state. Although it could enable exceptionally fine control over the energetic properties of solid-state devices, its molecular mechanisms have remained largely unexplored. We use ultrafast transient absorption and optical Kerr effect spectroscopies to independently track and correlate both the excited-state dynamics of an organic emitter and the polarization anisotropy relaxation of a small polar dopant embedded in an amorphous polystyrene matrix. The results demonstrate that the dopants are able to rotationally reorient on ultrafast time scales following light-induced changes in the electronic configuration of the emitter, minimizing the system energy. The solid-state dopant emitter dynamics are intrinsically analogous to liquid-state solvent solute interactions. In addition, tuning the dopant/polymer pore ratio offers control over solvation dynamics by exploiting molecular-scale confinement of the dopants by the polymer matrix. Our findings will enable refined strategies for tuning optoelectronic material properties using SSS and offer new strategies to investigate mobility and disorder in heterogeneous solid and glassy materials.

Solid-state solvation (SSS) is analogous to liquid-phase solvation but occurs within glassy matrices. Organic solutes with singlet charge transfer (1CT) excited states are especially susceptible to solvatochromism. Their 1CT states and photon emission energies decrease when surrounding molecules with sterically unhindered polar moieties reorient to stabilize them. Thermally activated delayed fluorescence (TADF) organic light-emitting diodes feature such solutes as emitters in the solid state, employing efficient reverse intersystem crossing to harvest the majority of electrogenerated triplets. Here we explore the potential of SSS to manipulate not only these emitters’ 1CT states but also, concurrently, their singlet–triplet energy gaps (ΔEST) that control TADF. By solvating the TADF emitter 2PXZ-OXD with progressively increasing concentrations of camphoric anhydride (CA) in a polystyrene film, we find that it is possible to finely tune the emitter’s photophysics. We observe a maximum increase in prompt li...

As new tools and techniques have become available, the expansion of high throughput experimentation into the broader chemical community has occurred, with the application of this infrastructure moving beyond biologically focused research and into the mainstream of materials and catalytic research. The study of homogeneous catalysis has been significantly impacted by the application of high throughput research. For research problems where the number of variables are very high, these tools are ideally suited to significantly increase the experimental output and speed the time for discovery and development of new catalysts and catalytic applications. In addition, high throughput experimentation provides for an opportunity to conduct a much more diverse structure activity study of new catalyst families and, with the greater experimental throughput, allows researchers to explore more out of the box solutions. In this Comment, the impact of homogeneous catalysis high throughput research at The Dow Chemical Company and in the broader catalysis community will be reviewed and examples of high throughput research towards the major areas in this field will be highlighted.