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Nitrogen-15 nuclear magnetic resonance spectroscopy. NH proton exchange reactions of urea, thiourea, acetamide and thioacetamide

✍ Scribed by Yu Chun; Issa Yavari; John D. Roberts

Publisher
John Wiley and Sons
Year
1982
Tongue
English
Weight
264 KB
Volume
18
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

Measurements are reported of NH exchange rates of urea, thiourea, acetamide and thioacetamide, using line‐shape analysis with natural‐abundance ^15^N NMR spectra. Base‐catalyzed NH‐proton exchange of thiourea is 30–40 times faster than for urea, while the corresponding acid‐catalyzed exchange is 150 times slower. The base‐catalyzed proton exchange for thioacetamide is about 1000 times faster than that of acetamide at 25°C, while the corresponding acid‐catalyzed exchange is some 260 times slower.

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