Self-assembled thermoreversible gels of nonpolar liquids by racemic propargylic alcohols with fluorinated and nonfluorinated aromatic rings.
The synthesis and colloidal study of a new class of low molecular weight organogelators is reported. Racemic propargylic alcohols with perfluoroaryl and nonfluorinated aryl rings are capable of forming gels in alkane liquids and/or silicone oil. A full colloidal characterization of alkane gels prepared from (R/S)-1-pentafluorophenyl-3-phenylprop-2-yn-1-ol [(R/S)- 1] was conducted, including both structural [optical microscopy, scanning electron microscopy (SEM), powder X-ray diffraction (XRD), attenuated total reflectance infrared spectroscopy (ATR-IR)] and thermal stability [differential scanning calorimetry (DSC)] studies. A model of the organization of gelator molecules within gel fibers has been proposed primarily based on the correlation of diffraction data for the powder XRD pattern of a gel and a simulated powder pattern from a sublimed crystal of the gelator. Furthermore, structural requirements for propargylic alcohol gelators were investigated by subjecting derivatives with modified structures to gelation tests. An enantiomerically enriched sample [(R)- 1, 83% ee] fails to entrap the solvent under conditions where the racemate successfully forms a gel. The remaining racemic derivatives (with p-alkoxy or p-alkyl substituents on the nonfluorinated arene) form gels or partial gels in silicone oil and in some alkane preparations.
Department of Chemistry and Biochemistry, James Madison University, Harrisonburg, Virginia 22807, USA.
Ashleigh R
AR
Borges
Marilise
M
Hyacinth
Michelle
M
Lum
Clayton M
CM
Dingle
Paris L
PL
Hamilton
Maksymilian
M
Chruszcz
Lin
L
Pu
Michal
M
Sabat
Kevin L
KL
Caran
D000480:Alkynes / Q000138:chemical synthesis / Q000737:chemistry*; D018360:Crystallography, X-Ray; D017611:Fluorine Compounds / Q000737:chemistry*; D005782:Gels / Q000737:chemistry; D007536:Isomerism; D008855:Microscopy, Electron, Scanning; D008958:Models, Molecular; D015394:Molecular Structure; D044367:Phase Transition; D020005:Propanols / Q000138:chemical synthesis / Q000737:chemistry*; D013057:Spectrum Analysis; D013696:Temperature
D000480:Alkynes; D017611:Fluorine Compounds; D005782:Gels; D020005:Propanols; C028255:propargyl alcohol