The long-standing challenge of designing and constructing new crystalline solid-state materials from molecular building blocks is just beginning to be addressed with success. A conceptual approach that requires the use of secondary building units to direct the assembly of ordered frameworks epitomizes this process: we call this approach reticular synthesis. This chemistry has yielded materials designed to have predetermined structures, compositions and properties. In particular, highly porous frameworks held together by strong metal-oxygen-carbon bonds and with exceptionally large surface area and capacity for gas storage have been prepared and their pore metrics systematically varied and functionalized.

/pdf/reticular-synthesis-and-the-design-of-new-materials-lazbx7tdux.pdf

Reticular synthesis and the design of new materials

N-Heterocyclic carbenes have become universal ligands in organometallic and inorganic coordination chemistry. They not only bind to any transition metal, be it in low or high oxidation states, but also to main group elements such as beryllium, sulfur, and iodine. Because of their specific coordination chemistry, N-heterocyclic carbenes both stabilize and activate metal centers in quite different key catalytic steps of organic syntheses, for example, C-H activation, C-C, C-H, C-O, and C-N bond formation. There is now ample evidence that in the new generation of organometallic catalysts the established ligand class of organophosphanes will be supplemented and, in part, replaced by N-heterocyclic carbenes. Over the past few years, this chemistry has been the field of vivid scientific competition, and yielded previously unexpected successes in key areas of homogeneous catalysis. From the work in numerous academic laboratories and in industry, a revolutionary turning point in oraganometallic catalysis is emerging.

http://aether.cmi.ua.ac.be/artikels/Artikels%20Gitte/Artikels/Reviews/NHC-%20liganden%20Herrmann.pdf

N-heterocyclic carbenes: a new concept in organometallic catalysis.

http://yaghi.berkeley.edu/pdfPublications/04MOFs.pdf

Metal-organic frameworks: a new class of porous materials

B. Anionic Ligands 302 IX. Group 9 Catalysts 302 X. Group 10 Catalysts 303 A. Neutral Ligands 303 1. R-Diimine and Related Ligands 303 2. Other Neutral Nitrogen-Based Ligands 304 3. Chelating Phosphorus-Based Ligands 304 B. Monoanionic Ligands 305 1. [PO] Chelates 305 2. [NO] Chelates 306 3. Other Monoanionic Ligands 306 4. Carbon-Based Ligands 306 XI. Group 11 Catalysts 307 XII. Group 12 Catalysts 307 XIII. Group 13 Catalysts 307 XIV. Summary and Outlook 308 XV. Glossary 308 XVI. References 308

/pdf/advances-in-non-metallocene-olefin-polymerization-catalysis-abl2neq5j1.pdf

Advances in non-metallocene olefin polymerization catalysis.

A carbon dioxide storage system includes a container and a conduit attached to the container for introducing or removing a carbon dioxide-containing composition from the container. A carbon dioxide storage material is positioned within the container. The carbon dioxide-storage material includes a metal-organic framework, which has a sufficient surface area to store at least 10 carbon dioxide molecules per formula unit of the metal-organic framework at a temperature of about 25° C.

Metal-organic frameworks with exceptionally high capacity for storage of carbon dioxide at room-temperature

The reactions of aryl bromides with amines occurs at room temperature when using Pd(0) and P(t-Bu)(3) in a 1:1 ratio, and the reactions of aryl chlorides occur at room temperature or 70 degrees C. The arylation of indoles and the new arylation of carbamates also occur when using P(t-Bu)(3) as ligand.

Room-Temperature Palladium-Catalyzed Amination of Aryl Bromides and Chlorides and Extended Scope of Aromatic C−N Bond Formation with a Commercial Ligand

High turnover number and rapid, room-temperature amination of chloroarenes using saturated carbene ligands.

Studies on the assembly of metal -organic frameworks (MOFs) have uncovered methods to build extended structures from molecular building blocks. 1-3 The synthesis of a new type of porous material using strategies based on the expansion and decoration of vertexes in basic nets has demonstrated the wide scope of this chemistry. 4 In particular, crystalline MOFs that maintain their open structure in the absence of guests can perform highly selective separations. 5

Tertiary building units: synthesis, structure, and porosity of a metal-organic dendrimer framework (MODF-1).

The search for a model that can be used to describe the optical excitation migration in dendrimers has attracted great attention. In most cases in a dendrimer the conjugation is disrupted at the branching point; however, the excitation is delocalized. The strength of interactions among neighboring chromophores plays a key role in determining the energy migration mechanism. Conversely, having many identical chromophores held tightly together in an ordered macromolecular architecture will allow for many dipoles to be accessible for optical excitation. Therefore, the relative orientation of dipoles will be important in determining the mechanism of energy migration. Here we report the synthesis and photo-physical investigation of triarylamine-based dendrimers. Two important synthetic steps were utilized in the synthesis. First, we employed diphenylmethyl protective groups on the amines to assist in deprotective hydrogenolysis of the larger structures. Second, highly active catalysts for formation of both di- and triarylamines that are based on a 1:1 ratio of P(t-Bu)3 and Pd(dba)2 improved reaction yields of the C-N bond formation and decreased reaction times The energy migration processes in the dendrimers were investigated utilizing ultrafast time-resolved fluorescence anisotropy measurements. The fluorescence anisotropy of all three dendrimers decayed to a residual value within approximately 100 fs. This fluorescence anisotropy decay showed a general trend in decreasing with increasing dendrimer generation. The residual anisotropy value also showed a gradual decrease with an increase in the dendrimer generation. This fast energy depolarization is discussed through a coherent excitonic mechanism among dipoles oriented in different directions. We believe that the formation of coherent domains leads to fast energy migration extending over a large part of the dendrimer.

Sheila I. Hauck

Papers

Room-Temperature Palladium-Catalyzed Amination of Aryl Bromides and Chlorides and Extended Scope of Aromatic C−N Bond Formation with a Commercial Ligand

High turnover number and rapid, room-temperature amination of chloroarenes using saturated carbene ligands.

Tertiary building units: synthesis, structure, and porosity of a metal-organic dendrimer framework (MODF-1).

Femtosecond excitation energy transport in triarylamine dendrimers.

Tetraazacyclophanes by Palladium-Catalyzed Aromatic Amination. Geometrically Defined, Stable, High-Spin Diradicals