Organometallic Chemistry Introduction Textbook H: Chapters 1.1 - 1.3.4 Textbook A: Introduction, History, Chapters 1.1 - 1.3 Office hours: after class Paula Diaconescu TA: Wenliang Huang E-mail: pld@chem.ucla.edu; huangwenl@ucla.edu

Textbooks Required texts: Recommended: Organotransition metal chemistry: From bonding to catalysis by John F. Hartwig, University Science Books, 2010 Organometallic chemistry and catalysis by Didier Astruc, Springer, 2007 UCLA subscription: http://www.springerlink.com/content/r36568/ Recommended: Organometallics 1: Complexes with Metal-Carbon s Bonds and Organometallics 2: Complexes with Metal-Carbon p Bonds by Manfred Bochmann, Oxford University Press, 1993 (beginner level) Applied Organometallic Chemistry and Catalysis by Robin Whyman, Oxford University Press, 2003 (beginner level) Organometallic Chemistry by Gary O. Spessard and Gary L. Miessler, Prentice Hall, Inc., 1997 (intermediate level) The Organometallic Chemistry of the Transition Metals by Robert H. Crabtree, Wiley Interscience; 2nd edition – 1994 or 3rd edition - 2005 (advanced level) Homogeneous Catalysis; Understanding the art by Piet W. N. M. van Leeuwen, Kluwer Academic Publishers, 2004 (advanced level) Article references given during lecture http://www.ilpi.com/organomet/index.html

Grading Grading: Winter organometallic seminars: Midterm: 30% Final: 50% Literature presentation: 20% (10% for content, 5% for answering questions, 5% for asking questions) Bonus (calculated based on the highest grade): 5% for writing a paper on a given topic + 5% for writing an original proposal undergraduates: 5% for attending all seminars listed below all: 5% for asking at least 5 good questions during the seminars listed below Winter organometallic seminars: 2/22/2012: Zhaomin Hou, RIKEN Advanced Science Institute  2/29/2012: Parisa Mehrkhodavandi, University of British Columbia 3/7/2012: Davit Zargarian, University of Montreal 3/14/2012: Malcolm Chisholm, Ohio State University

Administrative details All lecture notes will be posted before class on http://vohweb.chem.ucla.edu/voh/ Questions: http://vohweb.chem.ucla.edu/voh/ Midterm: February 3 (revision on Jan 30 in class) Literature presentations are on Mondays. First presentation will be on January 23. There will be no classes on Jan 16 and Feb 20 (university holidays). TA’s discussion section: Tuesday, 1-2 pm, YH 1337 TA’s office hours: Wednesday, 6-7pm, MSB1210

Frontiers in organometallic chemistry Definition of organometallic chemistry: transformations of organic compounds using metals. Organometallic chemistry is at the interface between inorganic and organic chemistry. Inorganic: subset of coordination chemistry Organic: subset of synthetic methods Other interdisciplinary areas Bioorganometallic chemistry Surface organometallic chemistry Fullerene-metal complexes

Energy Consumption, 2009 Our society has achieved a high degree of life comfort and is always putting pressure on the environment in order to sustain, expand, and provide it with sufficient energy. As scientists in general and chemists in particular, our duty is to make the processes needed to convert energy safer and more efficient than they are today. The global economic recession that began in 2008 and continued into 2009 has had a profound impact on world energy demand in the near term. Total world marketed energy consumption contracted by 1.2 percent in 2008 and by an estimated 2.2 percent in 2009, as manufacturing and consumer demand for goods and services declined. It is projected, however, that world marketed energy consumption increases by 49 percent from 2007 to 2035. Total energy demand in developing countries increases by 84 percent, compared with an increase of 14 percent in developed countries. Fossil fuels are expected to continue supplying much of the energy used worldwide. Although liquid fuels remain the largest source of energy, the liquids share of world marketed energy consumption falls from 35 percent in 2007 to 30 percent in 2035, as projected high world oil prices lead many energy users to switch away from liquid fuels when feasible. Liquids remain the world’s largest energy source, given their importance in the transportation and industrial end-use sectors. For the present and foreseeable future, the major source of energy for the nation is found in chemical bonds. http://www.eia.doe.gov/oiaf/ieo/highlights.html

Catalysis for Energy Understand mechanisms and dynamics Design and control the synthesis of catalyst structures Chemical catalysis affects our lives in myriad ways. Catalysis is the key to realizing environmentally friendly, economical processes for the conversion of fossil energy feedstocks. Catalysis also is the key to developing new technologies for converting alternative feedstocks, such as biomass, carbon dioxide, and water. Today, our nation faces a variety of challenges in creating alternative fuels, reducing harmful by-products in manufacturing, cleaning up the environment and preventing future pollution, dealing with the causes of global warming, protecting citizens from the release of toxic substances and infectious agents, and creating safe pharmaceuticals. Catalysts are needed to meet these challenges, but their complexity and diversity demand a revolution in the way catalysts are designed and used. A DOE report in 2007 identified a number of challenges such that catalytic process can help solving the energy problem. The first grand challenge identified in this report centers on understanding mechanisms and dynamics of catalyzed reactions. Catalysis involves chemical transformations that must be understood at the atomic scale because catalytic reactions present an intricate dance of chemical bond-breaking and bond-forming steps. Structures of solid catalyst surfaces, where the reactions occur on only a few isolated sites and in the presence of highly complex mixtures of molecules interacting with the surface in myriad ways, are extremely difficult to describe. The second grand challenge in the report centers on design and controlled synthesis of catalyst structures. Fundamental investigations of catalyst structures and the mechanisms of catalytic reactions provide the necessary foundation for the synthesis of improved catalysts. Theory can serve as a predictive design tool, guiding synthetic approaches for construction of materials with precisely designed catalytic surface structures at the nano and atomic scales. Success in the design and controlled synthesis of catalytic structures requires an interplay between (1) characterization of catalysts as they function, including evaluation of their performance under technologically realistic conditions, and (2) synthesis of catalyst structures to achieve high activity and product selectivity. DOE workshop 2007

Catalysis Environmental : green chemistry, atom efficiency, waste remediation, recycling Polymeric materials: new polymers and polymer architectures, new monomers, new processes Pharmaceuticals and fine chemicals: demand for greater chemo-, regio-, stereo-, and enantioselectivity Feedstocks: practical alternatives to petroleum and natural gas The reason catalysis is so important to solving the energy problem is because catalysis is the essential technology for accelerating and directing chemical transformations. Catalysts vary in composition from solid metal surfaces to enzymes in solution, and they are involved in chemical transformations as different as the refining of petroleum and the synthesis of pharmaceuticals. Catalysis is involved in almost every aspect of our lives: it is important from reducing our impact on the environment to creating new polymeric materials and pharmaceuticals and better utilizing current feedstocks. Thus, it lies at the heart of our quality of life: The reduced emissions of modern cars, the abundance of fresh food at our stores, and the new pharmaceuticals that improve our health are made possible by chemical reactions controlled by catalysts. Catalysis is also essential to a healthy economy: The petroleum, chemical, and pharmaceutical industries, contributors of $500 billion to the gross national product of the United States, rely on catalysts to produce everything from fuels to “wonder drugs” to paints to cosmetics. By using efficient and selective catalytic processes, less energy is necessary.

History: first organometallic compound 1760 Louis Claude Cadet de Gassicourt (Paris) investigates inks based on cobalt salts and isolates cacodyl from cobalt minerals containing arsenic (CoAs2 and CoAsS2) : As2O3 + 4 CH3COOK  [AsMe2]2 first organometallic compound See editorial: Organometallics 2001, 20, 1488 -1498 Timeline: 1751 - Benjamin Franklin: Lightning is electrical 1767: Carbonated water: Joseph Priestley 1778 - Antoine Lavoisier (and Joseph Priestley): discovery of oxygen leading to end of Phlogiston theory

First transition metal organometallic compound 1827 Zeise’s salt is the first platinum - olefin complex See editorial: Organometallics 2001, 20, 2-6 Timeline: 1827: Friction match: John Walker 1827: Fountain-pen : Petrache Poenaru 1827 - Georg Ohm: Ohm's law (Electricity) 1827 - Amedeo Avogadro: Avogadro's law (Gas laws) 1828 - Friedrich Wöhler synthesized urea, destroying vitalism 1829: Steam locomotive: George Stephenson

History: 1900 – 1950 1863 Charles Friedel and James Crafts prepare organochlorosilanes 1890 Ludwig Mond discovers Ni(CO)4 1893 Alfred Werner develops the modern ideas of coordination chemistry 1899 introduction of Grignard reagents 1912 Nobel prize Victor Grignard and Paul Sabatier 1917 Schlenk prepares Li alkyls via transalkylation from R2Hg 1930 Ziegler and Gilman simplify organolithium preparation, using ether cleavage and alkyl halide metallation, respectively

History: 1950 – 1960 1951 – 1952 Discovery of ferrocene, Fe(h5-C5H5)2 Keally, Pauson, and Miller report the synthesis Wilkinson and Woodward report the correct structure 1973 Nobel prize Geoffrey Wilkinson and Ernst Otto Fischer on sandwich compounds 1955 Ziegler and Natta develop olefin polymerization at low pressure using mixed metal catalysts (transition metal halide / AlR3)

Ziegler/Natta polymerization Giulio Natta: Italian chemist, Nobel prize 1963 Learned of Ziegler’s research, and applied findings to other a-olefins such as propylene and styrene. Resulting polypropylene was made up of two fractions: amorphous (atactic) and crystalline (tactic). Polypropylene is not produced in radical initiated reactions. Control of polymer tacticity: 1963 Nobel prize for Karl Ziegler and Giulio Natta on Ziegler-Natta catalysts http://www.nobel.se/chemistry/laureates/1963/

History: 1960 – 1980: catalysis 1962: Vaska’s complex 1964: Fischer reports the first metal carbene.

History: olefin metathesis 1964: Banks reports the first example of olefin metathesis. 1971: Yves Chauvin proposes mechanism. 1974: Schrock synthesizes first metal alkylidene complex.

2005 Nobel prize in chemistry

2010 Nobel prize in chemistry Akira Suzuki

2010 Nobel prize in chemistry Richard F. Heck Ei-ichi Negishi

Ligands in organometallic chemistry Neutral 2e donors: PR3 (phosphines), CO (carbonyl), R2C=CR2 (alkenes), RC≡CR (alkynes, can also donate 4e), N≡CR (nitriles) Anionic 2e donors: X- (halide), CH3- (methyl), CR3- (alkyl), Ph- (phenyl), H- (hydride) The following can also donate 4e if needed, but initially count them as 2e donors (unless they are acting as bridging ligands): OR- (alkoxide), SR- (thiolate), NR2- (inorganic amide), PR2- (phosphide) Anionic 4e donors: C3H5- (allyl), O2- (oxide), S2- (sulfide), NR2- (imide), CR22- (alkylidene) and from the previous list: OR- (alkoxide), SR- (thiolate), NR2- (inorganic amide), PR2- (phosphide) Anionic 6e donors: Cp- (cyclopentadienyl), O2- (oxide) Z ligands: do not bring e to the metal: BR3, AlR3

hx kx mx Nomenclature h5-Cp h3-Cp h3-allyl h1-allyl h1-dppe / k1-dppe - bridging ligand

Ordering: from ACS publications In formulas with Cp (cyclopentadienyl) ligands, the Cp usually comes first, followed by the metal center: Cp2TiCl2 Other anionic multi-electron donating ligands are also often listed in front of the metal. In formulas with hydride ligands, the hydride is sometimes listed first. Rule # 1, however, takes precedence over this rule: HRh(CO)(PPh3)2 and Cp2TiH2 Bridging ligands are usually placed next to the metals in question, then followed by the other ligands Note that rules 1 & 2 take precedence: Co2(m-CO)2(CO)6, Rh2(m-Cl)2(CO)4, Cp2Fe2(m-CO)2(CO)2

Coordination geometries CN Geometry Example 2 3, trigonal 3, T shape 4, tetrahedron 4, square planar [NC–Ag–CN]– Pt(PPh3)3 [Rh(PPh3)3]+ Ti(CH2Ph)4

Coordination geometries CN Geometry Example 5, trigonal bipyramid 5, square pyramid 6, octahedron 6, pseudo-octahedron [Co(CNPh)5]2+ W(CO)6 FeCp2

Coordination geometries CN Geometry Example 6, antiprism 7, capped octahedron 7, pentagonal biprism WMe6 [ReH(PR3)3(MeCN)3]+ [IrH5(PPh3)2]