Research Symposium

BIO

Dedicated pre-med student passionate about the intersection of science and patient care. Actively involved in research, exploring medical advancements while developing a strong foundation in healthcare.

Kinetic Isotope Effects in the Photoisomerization of ¹³C-Labeled trans,trans-1,4-Diphenyl-1,3-Butadiene

Abstract

All-trans−β-carrotene, composed entirely of 13C, undergoes 2Ag
excited state decay 1.43 times slower than natural β-carrotene.1
Differences in C-C stretching frequencies between excited and
ground state account for this result.1 We wish to determine
whether a 13C kinetic isotope effect is also present when the
excited state decays primarily via torsional motion. We will carry
out a 1H NMR study of the photoisomerization of
trans,trans-1,4-diphenyl-1,3-butadiene (tt-DPB) labelled with
13C at the 1 position. 1H NMR analysis of the cis,trans-1,4-
diphenyl-1,3-butadiene (ct-DPB) photoproduct should reveal the
relative torsional relaxation rates of the 12C12C and 13C12C double
bonds. tt-DPB-13C is already on hand.2 We plan to compare the
photochemical and photophysical properties of tt-DPB-13C to
those of natural tt-DPB.

Keywords: Photochemistry, Chemistry, Kinetics