Bibliography: p. 84-86. / The acid catalysed hydrolysis of a number of ring alkyl substituted dimethyl N-aryl phosphoramidates, (MeO)2P(0)NHAr, has been studied by measuring the rates of hyd~olysis with the aid of a UV spectrophotometer. These rates have been correlated with the pKa values of the corresponding ani I inium iOhs and the slope of this reactivitybasicity relationship for phosphoramidate with ortho substituents (6 = 0~85) is found to differ from that for substrates with meta and para substituents (S = 0,36). Determination of the thermodynamic parameters indicates that the entropy of activation is approximately constant for the substrates studied and the strongly negative values ~ -I -I (~S = 155,4 - 17,5 J mole K ) are consistent with an A2 type mechanism.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:uct/oai:localhost:11427/13518 |
| Date | January 1981 |
| Creators | Rijkmans, Bloys Peter |
| Contributors | Modro, Tom A |
| Publisher | University of Cape Town, Faculty of Science, Department of Chemistry |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Master Thesis, Masters, MSc |
| Format | application/pdf |
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