NMR MEASUREMENTS OF PROTON EXCHANGE IN AQUEOUS THIOUREA.
Abstract
The semiclassical lineshape expression of Hahn, Maxwell and McConnell for chemical exchange between two unequally populated sites is extended to the case where spin 1/2 nuclei in one site are coupled to a relaxing nucleus of spin I. The lineshape expression is written in closed algebraic form for spin I=1 and I=3/2. Experimental results are reported for acid catalyzed protolysis of aqueous thiourea. Possible exchange reactions are discussed. Water linewidths are used to derive rate parameters. The rate law for acid catalyzed protolysis of aqueous thiourea was found. Protolysis of thiourea N-H protons is concluded to be catalyzed about 60 times more efficiently than N-methyl acetamide N-H protons. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 12, 1969
- Accession Number
- AD0696744
Entities
People
- Adolfo Correa
- R. L. Vold
Organizations
- University of California, San Diego