James Fraser Stoddart

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J Fraser Stoddart
Born May 24, 1942
Edinburgh, Scotland, UK
Residence UK, USA
Field supramolecular chemistry
Institution University of California, Los Angeles, Birmingham University
Alma Mater Edinburgh University
Known for Mechanically-interlocked molecular architectures

James Fraser Stoddart is a British chemist at the Department of Chemistry and Biochemistry University of California, Los Angeles. He works in the area of supramolecular chemistry and nanotechnology. Stoddart has developed highly efficient syntheses of mechanically-interlocked molecular architectures such as molecular Borromean rings, catenanes and rotaxanes utilizing molecular recognition and self-assembly processes. He has demonstrated that these topologies can be employed as molecular switches and as motor-molecules. His group has even applied these structures in the fabrication of nanoelectronic devices and NanoElectroMechanical Systems (NEMS). His efforts have been recognized by numerous awards.[1]

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[edit] Biography

Fraser Stoddart was born 24 May 1942 in Edinburgh Scotland. Stoddart received his B.Sc. (1964) and Ph.D. (1966) degrees from Edinburgh University. In 1967, he went to Queen’s University (Canada) as a National Research Council Postdoctoral Fellow, and then, in 1970, to Sheffield University as an Imperial Chemical Industries (ICI) Research Fellow, before joining the academic staff as a Lecturer in Chemistry. He was a Science Research Council Senior Visiting Fellow at the University of California, Los Angeles (UCLA) in 1978. After spending a sabbatical (1978-81) at the ICI Corporate Laboratory in Runcorn, he returned to Sheffield where he was promoted to a Readership in 1982. He was awarded a DSc degree by Edinburgh in 1980 for his research into stereochemistry beyond the molecule. In 1990, he moved to the Chair of Organic Chemistry at Birmingham University and was Head of the School of Chemistry there (1993-97) before moving to UCLA as the Saul Winstein Professor of Chemistry in 1997. In July 2002, he became the Acting Co-Director of the California NanoSystems Institute (CNSI). On May 1, 2003, he was appointed the Director of the CNSI and assumed the Fred Kavli Chair of NanoSystems Sciences.

[edit] Research interests

Professor Stoddart work primarily in four different areas: (1) unnatural product synthesis that is either kinetically or thermodynamically controlled; (2) physical organic chemistry, principally as it relates to chemical topology and supramolecular phenomena; (3) design and construction of artificial molecular machinery, with actuators and switches particularly in mind; (4) the application of nanoscale chemistry to fundamental problems at the interfaces with materials science and the life sciences. His interests might be generally described as physical organic chemistry, which he describes as being about the three Ms — Making, Measuring and Modeling. His group engages in collaborations on the campus of campus wide and with groups at other universities.

One of his major contributions to the development of mechanically-interlocked molecular architectures has been the establishment of efficient synthesis of these molecules based on the binding of cyclobis(paraquat-p-phenylene). Using these efficient procedures his group has synthesized a variety of molecular machines. These molecular machines operate based on the movement of the various component, which are connected through a mechanical bonds. The mechanical bond holds the two components together while still allowing them to move relative to each other. These movements include linear motion such as sliding of the ring component along the rod of the dumbbell component of a [2]rotaxane in a molecular shuttle or a rotary manner as in the circumrotation of one ring through the other ring as in a [2]catenane. The motion allows the molecules to exist in multiple states making them suitable for used as a switches as well as linear motors and rotary motors. He has demonstrated that these molecular machines can be controlled chemically, electrically, and optically.

Stoddart has pioneered the use of mechanically-interlocked molecular architectures to create nanomechanical systems. He has demonstrated that such devices can be fabricated using a combination of the bottom-up approach of self-assembly and a top-down approachs of lithography and microfabrication. These molecular machines have potential uses as sensors, actuators, amplifiers, and switches.

[edit] Style

Stoddart typically places a solid circle in the middle of the aromatic rings of the molecular structures he has reported. He also uses different colors to highlight different parts of the molecules. The different colors usually correspond to the different parts of a cartoon representation of the molecule, but are also used to represent specific molecular properties (blue, for example, is used to represent electron poor recognition units while red is used to represent the corresponding electron rich recognition units). Stoddart maintains this standardized color scheme across all of his publications and presentations, and his style has been adopted by other researchers reporting molecular machines based on his syntheses.

[edit] ISI Ratings

Three of his >750 publications have been cited over 500 times, seven over 300, 40 over 100, and 126 over 50. He has an h-index of 73. For the period from January 1995 to October 31, 2005, he is ranked by the Institute for Scientific Information as the third most cited chemist with a total of 12,760 citations from 303 papers at a frequency of 41.7 citations per paper. During 35 years, >260 PhD students and postdoctoral researchers have been trained in his laboratories, and >60 have subsequently embarked upon independent academic careers. The Institute for Scientific Information (ISI) also predicted that J Fraser Stoddart was a likely winner of the Nobel Prize in Chemistry along with George M. Whitesides and Seiji Shinkai for their contributions to molecular self-assembly.

[edit] Research Keywords

supramolecular chemistry, self-assembly, mechanically-interlocked molecular architectures, catenanes, rotaxanes, molecular Borromean rings, mechanical bond, cyclodextrins, molecular electronics, molecular machines, molecular switches

[edit] External links