• Home
• Programs
  • Undergraduate
  • Graduate
• Unique PhD
• Faculty
• Research
• Staff
• Contact Us
• Maps

  Martin Pomerantz       

Phone: 817-272-3811    FAX: 817-272-3808     E-mail: pomerantz@uta.edu     Office: 205 CRB     Personal Page

Awards:

Alfred P. Sloan Foundation Fellow (1971-1976)
W. T. Doherty Award, D/FW Section of the American Chemical Society (1997)
University Distinguished Record of Research Award (1997)

RESEARCH:

Organic Chemistry

We are studying 2,2'-bithiophenes with various substituents on the 3— and 3'—positions to examine thiophene-thiophene dihedral angles and barriers to rotation. We have shown theoretically, using ab-initio quantum mechanical calculations, that certain functional groups will stabilize distorted planar or nearly planar structures because of coulombic stabilization of polar resonance forms. This stabilization causes distortion of the molecules, reduced dihedral angles and low rotation barriers. We have also demonstrated theoretically that certain other substituents allow the bithiophene to be completely planar, even with head-to-head substitution.  
Synthetic routes to these distorted and planar bithiophenes and to completely planar, conjugated polythiophenes are being examined. We are also studying ester pyrolysis reactions to see if these reactions, which produce an alkene and a carboxylic acid, can made to occur at lower temperatures. Normally these pyrolyses require high temperatures and if the elimination temperatures can be lowered there would be many useful synthetic applications. Further, we are examining the synthesis, reactions and properties of organo-l⁵-phosphazenes (R₃P=N—R') and phosphine oxides (R₃P=O). These studies include multinuclear (¹⁷O, ¹⁵N, ³¹P, ¹³C) NMR spectroscopy, structural studies including X-ray structure determination and quantum mechanical calculations. We are not only interested in the structural features of these systems but also in their reactions, and in the development of new synthetic methodology involving these systems. Additionally, we are studying the reactions of carbenes and their precursor diazo compounds with other molecules such as ketenes. Ketenes can be formed during carbene reactions, by the Wolff rearrangement, and we are examining the reactions of the ketenes as well.

Polymer Chemistry

We are involved in the design, synthesis and study of highly conjugated organic polymers which can be electrically conducting or electroluminescent [produce light when put between a metal and a transparent (indium-tin oxide) electrode]. We are interested in studying how chemical modification of the monomers and polymers affects the electrical conductivity, the transparency and the light emitting properties of these materials. Further we are developing new synthetic methodology for the preparation of these polymers and monomers. Attempts to prepare completely planar polythiophenes, even those systems with head-to-head linkages, as described above, are being pursued. We are attempting to prepare low-bandgap polymers which, unlike higher bandgap polymers, will be relatively colorless and transparent in the electrically conducting state. We are also examining polythiophenes containing electron withdrawing groups and new ways to prepare polyaniline. We are particularly interested in preparing electrically conductive polyaniline by methods which will be suitable for melt-processing.  
                                       

Reresentative Publications:

Pomerantz, M.; Levanon, M.; Gu, X.; Dias, H. V. R. "Formation of Two Heterocyclic Dimers from Dimethyl Diazomalonate and Bis(methoxycarbonyl)carbene. Preparation and Trapping of Methoxy(methoxycarbonyl)ketene with Cyclopentadiene," Tetrahedron 1997, 53, 10019.

Pomerantz, M., "Low Band Gap Conducting Polymers," in Handbook of Conducting Polymers, 2nd Edition; Skotheim, T. A.; Elsenbaumer, R. L.; Reynolds, J. R., Eds.; Marcel Dekker: New York, 1998; Chapter 11, p 277.

Kasim, R. K.; Pomerantz, M.; Elsenbaumer, R. L. "A Simple Method for Fabricating Light-Emitting Diodes," Chem. Mater. 1998, 10, 235.  

Pomerantz, M.; Liu, M. L. "Synthesis and Properties of Poly[3-(w-bromoalkyl)thiophenes]," Synth. Met. 1999, 101, 95.

Pomerantz, M.; Cheng, Y.; Kasim, R. K.; Elsenbaumer, R. L. "Synthesis and Properties of Regioregular Poly(dialkyl [2,2'-bithiophene]-5,5'-diyl-4,4'-dicarboxylates)," Synth. Met. 1999, 101, 162.

Pomerantz, M.; Cheng, Y. "Ester Substituted Bithiophenes. Abnormally Low Dihedral Angle and Rotational Barrier Due to Dipolar Stabilization," Tetrahedron Lett. 1999, 40, 3317.

Pomerantz, M.; Chang, Y.; Kasim, R. K.; Elsenbaumer, R. L. "Poly(alkyl thiophene-3-carboxylates). Synthesis, Properties and Electroluminescence Studies of Polythiophenes Containing a Carbonyl Group Directly Attached to the Ring," J. Mater. Chem. 1999, 9, 2155.

Pomerantz, M.; Gu, X.; Zhang, S. X. "Poly(2-decylthieno[3,4-b]thiophene-4,6-diyl). A New Low Band Gap Conducting Polymer," Macromolecules, 2001, 34, 1817.

Pomerantz, M., Amarasekara, A. S. and Dias, H. V. R., "Synthesis and Solid State Structures of Dimethyl 2,2'-Bithiophenedicarboxylates", J. Org. Chem. 2002, 67, 6931.

Pomerantz, M.; Maldonado, T. A.; Black, T. D.; Johnson, D. H.; Waller, L. K.; Purvinis, G. M.; Sudduth, M. R. "Ionic Self-Assembled Thin Films for Second Order NLO Applications," Polym. Prepr. (Am. Chem. Soc., Div. Polym. Chem.) 2002, 43(No. 2) 562.

Sudduth, M. R., Fore, S. R., Johnson, D. H., Waller, L. K., Maldonado, T. A., Black, T. D. and Pomerantz, M. ,"Maker Fringe Measurements of Non-poled Ionic Self-Assembled Thin Films," OSA Trends in Optics and Photonics, Vol. 64, Organic Thin Films for Photonic Applications; Armistead, J. P.; Heflin, J. R.; Jen, A. K.-Y.; Norwood, R. A., Eds.; Optical Society of America: Washington, DC, 2002; p 14.

Pomerantz, M. “Planar 2,2’-bithiophenes with 3,3’- and 3,3’,4,4’-Substituents. A  Computational Study,” Tetrahedron Lett. 2003, 44, 1563.

Pomerantz, M. and Amarasekara, A. S "Studies of Planar Poly(3,4-disubstituted-thiophenes)," Synth. Met. 2003, 135-136, 245.

Pomerantz, M.; and Amarasekara,  A. S. “N-Alkyl-3,4-thiophenedicarboximide. Monomers, Dimers and Polymers,” in 19th International Congress of Heterocyclic Chemistry; Pergamon: Amsterdam, 2003: p. 292.

Amarasekara, A. S. and Pomerantz, M. “Synthesis and Study of Head-to-Tail Regioregular Poly(alkyl thiophene-3-carboxylates),” Synthesis 2003, 2255.

Pomerantz, M.; Liu, L.; Zhang, X. “Synthesis and Study of  Poly[3-(6-substitutedhexyl)thiophenes] and Poly[3-(12-substituteddodecyl)thiophenes] Containing Halogen and Sulfur Substituents,” Arkivoc In press.

Department of Chemistry and Biochemistry
The University of Texas at Arlington
Arlington, Texas 76019-0065, USA
Phone: 817-272-3171 | Fax: 817-272-3808
All rights reserved © 2006 The University of Texas at Arlington
 | Contact Us | Webmaster | Last updated: November 07, 2009