76233-27-7Relevant academic research and scientific papers
Photochemistry of Stilbene-Amine. Spin-Trapping Study
Lin, Chiou-Rong,Wang, Cheng-Nan,Ho, Tong-Ing
, p. 5025 - 5029 (2007/10/02)
2-Methyl-2-nitrosopropane (MNP) was used as a spin-trap reagent to study the radicals formed in the photochemical reaction of substituted trans-stilbenes (TS) with tertiary amines.Seven 1,2-(p,p'-disubstituted phenyl)ethyl radicals were trapped by MNP and isolated and identified by HPLC-EPR.The nitrogen hyperfine splitting constants (hfsc) of these radicals are linearly correlated with the Hammett substituent constants δp.There is also a linear correlation of the nitrogen hfsc with both the single δp parameter and the dual δR, δ1 parameters.The inductive and resonance effects are of equal importance.The correlation between proton hfsc and a single δp parameter is not linear.There is fair correlation between the β-proton hfsc and the dual parameters δR, δ1.The only fair correlation may be due to the large dihedral angle between the nitrogen ? orbital and the N-C-H plane.
Photochemical Addition of Tertiary Amines to Stilbene. Stereoelectronic Control of Tertiary Amine Oxidation.
Lewis, Frederick D.,Ho, Tong-Ing,Simpson, J. Thomas
, p. 1077 - 1082 (2007/10/02)
The photochemical addition reactions of seven nonsymmetrical tertiary amines with singlet trans-stilbene are described.Addition of methyldiisopropylamine or isopropyldimethylamine is highly selective for formation of the least substituted α-amino radical, whereas addition of several less highly branched amines is relatively nonselective.The product isotope effect for tert-butylmethyl(trideuteriomethyl)amine is 2.2+/-0.2.Product selectivity is determined by the orientation of the deprotonation of an aminium radical intermediate by the stilbene radical anion.Selectiveoxidation results from e stereoelectronic effect which is most evident w hen one more alkyl group is highly branched.
