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Background

Karen Goldberg attended Barnard College of Columbia University in New York City where she received her A.B degree. Following her undergraduate studies, she continued schooling at The University of California, Berkeley where she received her Ph.D. in Chemistry. After earning her Ph.D. she spent a postdoctoral year with Bruce Bursten at the Ohio State University, followed by joining the faculty at Illinois State University. In 1995, Karen Goldberg moved to the University of Washington where she remains today as a chemistry professor.

Awards & Activities

·      Editorial Advisory Board Member for Accounts of Chemical Research (2004-2009) and Organometallics (2008-2010)

·      Editorial Advisory Board for Inorganic Chemistry (2002-2004)

·      Closs Lecturer, University of Chicago (2001)

·      Alternate Councilor of the Inorganic Division of the American Chemical Society (1999-2001)

·      Alfred P. Sloan Research Fellow (1997-1999)

·      Union Carbide Innovation Recognition Program Award (1995-1996)

·      Henry Dreyfus Teacher-Scholar Award (1995)

·      National Institutes of Health Postdoctoral Fellow (1988-1989)

·      National Science Foundation Predoctoral Fellowship(1983-1986)  

Her research focus:

Activation of strong bond

CENTC (Center for Enabling New Technology through Catalysis) 

1)  Anti-Markovnikov Hydroamination of Alkenes

• Platinum(II) Olefin Hydroarylation Catalysts: Tuning Selectivity for

the anti-Markovnikov Product

Knowing the value of synthesis of linear anti-Markovnikov products, her research focuses on discovery of transition metal catalysts which helps in catalysis of anti-Markovnikov hydroamination of alkenes. In one of her research, she introduces a method to catalyze the hydroarylation of unactivated alkenes using pt (II) complexes with unsymmetrical pyrrolide ligands. Selectivity was provided by using benzene and 1-hexene and an optimized catalyst. The result was production of high olefin concentration using propylene as the substrate. 

2)   Harnessing and Making Molecular Oxygen

-Reactivation of various transition metal complexes with molecular oxygen

• Reactions of Pd and Pt Complexes with Molecular Oxygen

The activation of oxygen and five coordinate Pt(IV) species was found to involve cooperation between the metal center and the ligand. A vital component to this reaction is the way the ligand is able to bind to the oxygen molecule.

• Oxygen-Promoted C-H Bond Activation at Palladium

The functionalization of C-H bonds with oxygenase type catalysts are desirable. Pd0 complex reacts with O2 and becomes an oxygenated metal that promotes C-H bond cleavage and O-H bond formation. This reult gives a better understand of how oxygen and C-H bonds interact with palladium and benefit the development of metal-catalyzed oxygenase reactions.

• Regeneration of an Iridium(III) Complex Active for Alkane Dehydrogenation Using Molecular Oxygen

One of the main reason’s Karen’s group focuses on reacting oxygen with transition metals is due to its abundance and how inexpensive it is. Alkane dehydrogenation reactions are typically performed using an olefin as an oxidant. However, if oxygen was used as the oxidant, there would be advantages of both cost and environmental impact. Through their work involving high oxidation state Ir(111) complexes for alkane activation leads to an approach in developing alkane functionalization systems that use oxygen as a hydrogen acceptor.

3)   A New Generation of Electrophilic Oxidation Catalysts

• Methylplatinum(II) and Molecular Oxygen: Oxidation to Methylplatinum(IV) in Competition with Methyl Group Transfer to Form Dimethylplatinum(IV)

Part of Karen’s research follows Alexander E. Shilov’s discovery of platinum catalyzed alkane oxidation and began experimenting with other metals that have not been studied extensively but follow the Shilov system in order to obtain a similar result of converting alkanes to alcohols. Pt11 methyl complexes are key intermediates in both the Shilov methane oxidation system and in more recent catalytic Pt methane oxidation systems. Pt(IV) oxidizes the Pt11 Me species and forms a Pt(IV) Me complex.

• High Catalytic Efficiency Combined with High Selectivity for the Aldehyde-Water Shift Reaction using (para-cymene)Ruthenium Precatalysts

Another section of her research involves formation of alcohol, carboxylic acid, and other organic molecules from alkanes using platinum or late metals including ruthenium, iridium and rhodium. One of her studies focuses on aldehyde-water shift reactions in which the oxidation of aldehydes to carboxylic acids using water as an oxidant take place. Aldehyde-water shift reactions are considered to be a competent for aldehyde disproportionation. As a result, her studies came up with a method to use of a family of (p-cymene) ruthenium(II) diamine complexes as precatalyst to provide selectivity and high conversion of aldehydes to carboxylic acids over aldehyde disproportionation.  

• Base-Free Iridium-Catalyzed Hydrogenation of Esters and Lactones

Lithium aluminum hydride has been widely used as strong reducing reagent. However, it is known that it is difficult to reduce resonance stabilized carbonyl group present in esters and lactones to alcohols. It was then that her research group came up with idea of Hydrogenation of esters and lactones to form alcohol using base free metal-catalyzed complexes. The catalyst that gave rise to a high yield of formate esters is half-sandwich iridium bipyridine complexes. For this reaction to proceed, a turnover-limiting hydride transfer at high pressures of H2 was needed.

• Hydrogenation of Carboxylic Acids Catalyzed by Half-Sandwich Complexes of Iridium and Rhodium

The same half sandwich complexes of iridium and rhodium was used as competent catalysts to hydrogenate carboxylic acids under relatively mild conditions in another paper she published. The mechanism behind this reaction involves hydride transfer from catalyst to formic acid as the main part of the reaction.

 

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New developments in nanochemistry provide a variety of nanostructure materials with significant properties that are highly controlabke. Some of the other application of these nanostructure materials include SAMs and lithography, use of nanowires in sensors, and nanoenzymes.

One of the methods of nanolithography is use of self-assembled monolayers (SAM) which develops soft methodology. SAMs are long chain alkanethiolates that are self-assembled on gold surfaces making a well-ordered monolayer films¹. The advantage of this method is to create a high quality structure with lateral dimensions of 5 nm to 500 nm. In this methodology a patterned elastomer made of polydimethylsiloxane (PDMS) as a mask is usually used. In order to make a PDMS stamp, the first step is to coat a thin layer of photoresist onto a silicon wafer. The next step is to expose the layer with UV light, and the exposed photoresist is washed away with developer. In order to reduce the thickness of the prepolymer, the patterned master is treated with perfluoroalkyltrichlorosilane². These PDMS elastomers are used to print micron and submicron design chemical inks on both planar and curved surfaces for different purposes.

Scientist also devised a large number of nanowire compositions with controlled length, diameter, doping, and surface structure by using vapor and solution phase strategies.  These oriented single crystals are being used in semiconductor nanowire devices such as diodes, transistors, logic circuits, lasers and sensors. Since nanowires have one dimensional structure meaning large surface to volume ratio, the diffusion resistance decreases. In addition, their efficiency in electron transport which is due to the quantum confinement effect, make their electrical properties be influenced by minor perturbation³. Therefore, use of these nanowires in nanosensor elements increases the sensitivity in electrode response. As mentioned above, one dimensionality and chemical flexibility of the semiconductor nanowires make them applicable in nanolasers. Peidong Yang and his co-workers have done some research on room-temperature ultraviolet nanowire nanolasers in which the significant properties of these nanolasers have been mentioned. They have concluded that using short wavelength nanolasers have applications in different fields such as optical computing, information storage, and microanalysis⁴.

Nanostructure materials mainly used in nanoparticle-based enzymes have drawn attraction due to the specific properties they show. Very small size of these nano enzymes (1-100 nm) have provided them unique optical, magnetic, electronic, and catalytic properties. Moreover, the control of surface functionality of nano particles and predictable nanostructure of these small sized enzymes have made them to create a complex structure on their surface which in turn meet the needs of specific applications⁵.

Although nanotechneeology and particularly nanoparticle-based enzymes is still in its early development stage, and only a few experiments have been reported, scientists have shown interest in use of this field in design of biosensors, molecular electronics, medical diagnostics, and drug delivery⁶.

References:

1,2) Ozin, Geoffery A., Andre C. Arsenault, and Ludovico Cademartiri. Nanochemistry: A Chemical Approach to Nanomaterials. 2nd ed. N.p.: Royal Society of Chemistry, pg 59-62, 2009. Print.

3) Huang Xin, Xianzhen Yin, Junqiu Liu, Selenoprotein and Mimics, pg 289-302, 2012. Print.

4) Huang, H. Michael, Wu Yiying, Room Temperature Ultraviolet Nanowire Nanolasers: Science 292, 2001. Print.

5,6) Aravamudhan, Shyam, Development of micro/nanosensor elements and packaging techniques for oceanography, 2007. Print.