## Abstract ^13^C‐ and ^1^H‐NMR. spectra of __ortho__‐benzoquinone **1** and its methyl derivatives have been analysed. By means of heteronuclear double resonance experiments it is shown that assignments given in the literature for the olefinic carbon resonances of **1** and of a series of substitu
The mass spectra of [17-13C]phyllocladene and [3-13C]methylenecholestane—III
✍ Scribed by R. A. Cruz; R. C. Castillo; F. J. Garcia; R. I. Reed
- Publisher
- John Wiley and Sons
- Year
- 1977
- Tongue
- English
- Weight
- 243 KB
- Volume
- 12
- Category
- Article
- ISSN
- 1076-5174
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✦ Synopsis
Abstract
The mass spectra of [17‐^13^C]phyllocladene and [3‐^13^C]methylenecholestane have been examined. It is shown that there are some rearrangements at 70 e V as in the case of [17‐^13^C]kaurene. However, no extensive randomization is evident at the molecular ion level. The results are interesting because very little is known about ^13^C randomization in polycyclic aliphatic hydrocarbons. The percentage retention of label was calculated for each ion.
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