68120-92-3

Upstream product

• 57825-33-9 (1-13C)-phenylacetic acid 
• 2154-56-5 benzyl radical 

Downstream Products

• 100-44-7 benzyl chloride 
• 103-29-7 1,1'-(1,2-ethanediyl)bisbenzene 

Relevant academic research and scientific papers

Magnetic and Micellar Effects on Photoreactions. 1. 13C Isotopic Enrichment of Dibenzyl Ketone via Photolysis in Aqueous Detergent Solution

The photolysis of dibenzylketone (DBK) in homogeneous organic solutions and in micelle-containing detergent solutions has been investigated from the standpoint of determining the extent and location of 13C enrichment that occurs.In a series of experiments it is established that for incomplete conversions the residual, recovered DBK is enriched in 13C relative to the initial unphotolyzed DBK.The efficiency of the 13C/12C separation is shown to be characterized by an isotope enrichment parameter, α, which is independent of the extent of conversion.A combination of mass spectrometry and nuclear magnetic resonance spectroscopy provides support for the primary location of the 13C enrichment at C-1 (the carbonyl carbon) with a lesser but significant enrichment at C-2 (the methylene carbon).A very small but experimentally distinct enrichment of the aromatic rings is indicated by 13C NMR analysis.An isomer of DBK, 1-phenyl-4'-methylacetophenone (PMAP) is formed as a minor product of photolysis in micellar solutions.PMAP, like the recovered, residual DBK, is found to be substantially enriched in 13C relative to the starting DBK.The magnitude of α is found to be significantly influenced by the application of laboratory magnetic fields to the photolysis sample.The latter result, along with the unusually large magnitude of α, suggests that the mechanism involved in isotopic enrichment is not dominated by kinetic mass isotope effects but rather by nuclear magnetic moment and/or magnetic spin isotope effects.

Theoretical and experimental studies of chemically induced dynamic nuclear polarization kinetics in recombination of radical pairs by the method of switched external magnetic field. II.13C CIDNP of micellized radical pairs

The method of 13C chemically induced dynamic nuclear polarization in a switched external magnetic field (SEMF CIDNP) has been applied for the first time in an experimental investigation of micellized radical pairs (RP). Using the examples of three photochemical reactions it has been shown, that SEMF CIDNP allows the investigation of the kinetics of short-lived micellized RPs with high time-resolution in low and intermediate magnetic fields. The experimental kinetics have been analyzed and simulated on the basis of a previously developed theory [Parnachev et al, J. Chem. Phys. 107,9942 (1997)]. It has been demonstrated that such an analysis provides information on the rates of radical escape from the micelle, on electron relaxation and on the rate of S-T- transitions. The analysis of the estimated rates of 5-T_ transitions showed that the exchange interaction is essentially anisotropic in the RPs studied.