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How can you predict relative Rf values of cis-trans isomers in thin layer chromatography?
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+ Biochemistry
+ Chromatography
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Kevin Kolbe
How can you predict relative Rf values of cis-trans isomers in thin layer chromatography?
Well, apparently I was wrong.
In fact, the trans,trans isomer is adsorbed more strongly by the stationary phase because it is entirely planar. The cis,trans-isomer cannot adopt a planar conformation because of steric hindrance between the two phenyl rings. The non-coplanar geometry lowers the efficiency of interactions with the stationary phase, making it more mobile.
So the cis,trans isomer has a higher Rf, and the trans,trans isomer has a lower Rf.
In fact, the trans,trans isomer is adsorbed more strongly by the stationary phase because it is entirely planar. The cis,trans-isomer cannot adopt a planar conformation because of steric hindrance between the two phenyl rings. The non-coplanar geometry lowers the efficiency of interactions with the stationary phase, making it more mobile.
So the cis,trans isomer has a higher Rf, and the trans,trans isomer has a lower Rf.
Well, apparently I was wrong.
In fact, the trans,trans isomer is adsorbed more strongly by the stationary phase because it is entirely planar. The cis,trans-isomer cannot adopt a planar conformation because of steric hindrance between the two phenyl rings. The non-coplanar geometry lowers the efficiency of interactions with the stationary phase, making it more mobile.
So the cis,trans isomer has a higher Rf, and the trans,trans isomer has a lower Rf.
Well, apparently I was wrong.
In fact, the trans,trans isomer is adsorbed more strongly by the stationary phase because it is entirely planar. The cis,trans-isomer cannot adopt a planar conformation because of steric hindrance between the two phenyl rings. The non-coplanar geometry lowers the efficiency of interactions with the stationary phase, making it more mobile.
So the cis,trans isomer has a higher Rf, and the trans,trans isomer has a lower Rf.
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