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Paul F. Hudrlik

Professor

B.S. 1963, Oregon State University
M.A. 1964, Columbia University
Ph.D. 1968, Columbia University
Postdoctoral, 1968-69, Stanford University
 

ORGANIC CHEMISTRY
Synthetic Organic Chemistry, Organosilicon Chemistry, Molecular Recognition

EMAIL:  phudrlik (at) howard.edu

202-806-4245 (Voice)

202-806-5442 (FAX)

AWARDS

1967                Louis P. Hammett Award  (Columbia University)

1988                Cyanamid Academic Award

1996                Certificate of Recognition for “Outstanding and Meritorious Service and Contributions to the Honors Program”, Howard University.

2000                Millennium Award for Excellence in Teaching at Historically Black Colleges and Universities

2006                Graduate Faculty Productivity Award, Howard University

 PUBLICATIONS

Most of our current research is concerned with the development of new applications of organosilicon chemistry to organic synthesis. Although organosilicon compounds are structurally analogous to the corresponding compounds of carbon, in terms of reactivity they are more like hydrogen or metals. Organosilicon compounds are much less reactive than organometallic compounds of other elements, however, thus enabling some organosilicon compounds to serve as intermediates in multi-step organic syntheses. In the past decade the use of organosilicon compounds in synthetic organic chemistry has become widespread.

For some time we have been investigating the chemistry of carbon-functional organosilicon compounds, in order to gain a fundamental knowledge of the mechanism and stereochemistry of reactions of organosilicon compounds, and to develop methods which would be potentially useful for the synthesis of natural products and other biologically interesting molecules.

Elimination reactions of <beta>-hydroxysilanes are widely used for the synthesis of olefins. In 1974 we reported that these elimination reactions are stereospecific, and that the acid-catalyzed reactions are anti while the base-induced reactions are syn. Any method for preparing <beta>-hydroxysilanes of known stereochemistry is therefore a potential method for stereospecific olefin synthesis. Some of the most promising developments which have evolved from this idea are the following:

(1) We have shown that <alpha>,<beta>-epoxysilanes undergo regio- and stereospecific ring opening with many different types of reagents to give <beta>-hydroxysilanes, and can therefore be used as stereospecific vinyl cation equivalents for the synthesis of a variety of heteroatom-substituted olefins, some of which could not be prepared (stereospecifically) by existing methods.

(2) We have developed a method for preparing <alpha>-silyl aldehydes and have shown these compounds to be useful vinyl cation equivalents for the synthesis of <alpha>-vinyl carbonyl compounds. We hope to apply these findings to the synthesis of natural products and related compounds, such as quinine and unsaturated amino acids.

(3) We have found that Baeyer-Villiger reactions of cyclic ketones can be directed by silicon to give silyl lactones which are easily transformed into olefinic acids. We have applied this reaction to the synthesis of the insect pheromones frontalin and brevicomin and anticipate many other applications.

Additional current projects include the use of pentacoordinate silicon intermediates as templates in bond forming reactions, and applications of some of these reactions to asymmetric synthesis.

We are also interested in molecular recognition, and have been investigating the synthesis of potential host materials such as new types of calixarenes, as well as the study of their ability to complex guests. Much of this work is being carried out in conjunction with the Keck Center for the Design of Nanoscale Materials for Molecular Recognition at Howard University. Ultimately the attachment of effective host compounds to surfaces and polymeric compounds will be studied in collaboration with other members of the Center.