Crystalline molecular compasses: Incorporating dipoles into volume conserving rotators

ORGN 439

Steven D. Karlen, skarlen@chem.ucla.edu, Department of Chemistry and Biochemistry, University of California, Los Angeles, 405 Hilgard Avenue, Los Angeles, CA 90095 and Miguel A. Garcia-Garibay, mgg@chem.ucla.edu, Department of Chemistry and Biochemistry, UCLA, 405 Hilgard Ave, Los Angeles, CA 90025.
Molecular compasses consist of three components a stator, an axle, and a rotator. The rotational barrier can be tuned by varying these three components. The crystal packing and rotational dynamics of molecular rotors with p-phenylene rotators, diethynyl axles, and triptycyl and triphenyl-X stators (where X = C, Si, P, and B) have been tuned to give rotational barriers varying from greater than 20 kcal/mol down to 5 kcal/mol. This range of rotational barriers have also been achieved by using a triphenylsilyl stator and changing the rotator from the flat disk-like p-phenylene rotator (8-12 kcal/mol) to a more volume conserving cylindrically shaped p-carborane rotator (3.0 kcal/mol). In this poster we will report how adding dipoles to the p-phenylene, bicyclo[2.2.2]octane, and carborane rotators effects crystal packing and rotational dynamics, Figure 1.

 

New Reactions and Methodology, Total Synthesis, Materials, Devices and Switches, Lipids, Nucleotides and Mimetics
8:00 PM-10:00 PM, Tuesday, March 27, 2007 Hyatt Regency Chicago -- Riverside Center, Poster

Division of Organic Chemistry

The 233rd ACS National Meeting, Chicago, IL, March 25-29, 2007