Journal of the American Chemical Society p. 3886 - 3891 (1981)
Update date:2022-08-03
Topics:
Turro, Nicholas J.
Chow, Ming-Fea
Chung, Chao-Jen
Kraeutler, Bernhard
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.
View MoreNingbo Hi-tech Zone Nice-Synth Chemical Industry Ltd.
Contact:+86-(574)-81110986
Address:No. 1210, Building 3, Wante Business Centre, Hi-tech Zone, Ningbo
Changzhou Hopschain Chemical Co.,Ltd
website:http://www.hopschem.cn/products.html
Contact:86-519-85528066
Address:Room 710, Unit A, Xingbei Development Mansion, Tongjiang Road, Changzhou City,213000, China
Hubei Sky Lake Chemical Co., Ltd.
Contact:+86-27-87385545
Address:Te-2, Xijiao Chemical Park, Yuekou Town, Tianmen, Hubei, China.
Skyrun Industrial Co.,Ltd(expird)
website:http://www.chinaskyrun.com
Contact:0086-576-84610586
Address:Chemical Development Zone
Shandong Topscience Biotech Co., Ltd.
Contact:0633-2619278
Address:No. 98 Lanshan West Road, Lanshan District, Rizhao, Shandong Province, P.R. of China
Doi:10.1007/s00706-011-0670-8
(2012)Doi:10.1007/BF00948251
(1982)Doi:10.1080/00945710009351753
(2000)Doi:10.1016/S0040-4039(01)97767-6
(1970)Doi:10.1021/ja01209a053
(1946)Doi:10.1016/j.molcata.2015.08.003
(2015)