Synthesis and Characterization of Natural Abundance and Isotopically Labeled 1,4–Bis(3,3,3–triphenylpropynyl)–2,3–difluorobenzene. A Molecular Gyroscope with a Polar Rotator

Rosa Santillán,^1* Steven D. Karlen,² Hung Dang,² and Miguel A. Garcia–Garibay^2*

¹ Departamento de Química, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional, A.P. 14–740, 07000 México D.F., México. ^*Responsible author: rsantill@cinvestav.mx.

² Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095–1569, USA. ^*Responsible author: mgg@chem.ucla.edu.

Recibido el 4 de diciembre de 2007 ]]> Aceptado el 13 de mayo de 2008

Abstract

Sonogashira coupling of natural abundance and d₂–deuterated 1,4–bis(trifluoromethanesulfonate)–2,3–difluorobenzene provides access to 1,4–bis(3,3,3–triphenylpropynyl)–2,3–difluorobenzene, a structure that emulates a molecular gyroscope with a dipolar rotator. Two crystal forms of this compound are of interest for the construction of ferroelectric materials.

Key words: Molecular machines, molecular rotors, isotopic substitution, X–ray structure.

Resumen

Con un acoplamiento de tipo Sonogashira usando muestras de 2,3–difluorobenzeno–1,4–bis(trifluorometanosulfonato) en sus formas isotópicas de abundacia natural y deuterada, se prepararon muestras de 1,4–bis(3,3,3–trifenilpropinil)–2,3–difluorobenzeno. Este compuesto posee características similares a las de un giroscopio con un rotor dipolar. Las dos estructuras cristalinas obtenidas son de interés para preparar materials ferroeléctricos.

Palabras clave: Máquinas moleculares, rotores moleculares, substitución isotopica, estructura de rayos X.

Acknowledgments

This work was supported by the National Science Foundation through grants DMR0307028 and DGE–0114443 [NSF IGERT: Materials Creation Training Program (MCTP)]. Support for a sabbatical leave at UCLA to RS by CONACYT Mexico, and UC–MEXUS is also acknowledged.

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