Dynamic NMR and Twisted Intramolecular Charge Transfer Excited States

DOI: 10.4236/ajac.2015.65039   PDF   HTML   XML   3,260 Downloads   3,700 Views  


In this paper the results of dynamic NMR studies on ethylmethylamino-tertiary-butyl-phenylborane (EMABPB) with or without light are reported. The NMR data were recorded on a Bruker 400 MHz NMR equipped with our custom-made optical probe and with our custom-made 450 watts (W) monochromatic light sources. The molecular photochemistry including twisted intramolecular charge-transfer-excited-state (TICT) of the EMABPB in several solvents has been investigated. These results indicate that the aminoborane demonstrates multiple configurations in CD3Cl and CD2Cl2 resulting in the shifts of the signals of the alkyl groups on the nitrogen and boron. This indicates that there are some time-dependent changes at constant temperature over the irradiation interval. At ﹣60°C and the presence of light (λ = 265 nm), we observed a large change in the populations of the two sites, and this by itself indicates a modification in the rotation around the boron nitrogen bond in the excited state. By considering the existence of the TICT state, many important energy technologies may be developed with higher efficiency by controlling the back-electron transfer processes.

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Parchamazad, I. , Hornyak, D. and Miles, M. (2015) Dynamic NMR and Twisted Intramolecular Charge Transfer Excited States. American Journal of Analytical Chemistry, 6, 402-410. doi: 10.4236/ajac.2015.65039.

Conflicts of Interest

The authors declare no conflicts of interest.


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