Dipolar Cycloaddition Reactions of some Nickel(II) and Palladium(II) Azido Complexes
| Main Authors: | PARIMAL PAUL, SUKLA CHAKLADAR, KAMALAKSHA NAG |
|---|---|
| Format: | Article Journal |
| Bahasa: | eng |
| Terbitan: |
, 1985
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| Subjects: | |
| Online Access: |
https://zenodo.org/record/6322621 |
Daftar Isi:
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Calcutta-700 032 Azido complexes of the types NiL1-3 N2, PdL1-3N2 and [L1Ni-N2-NIL1][CIO4], where the princil at ligands HL1-3 contain N2S donor units, undergo facile 1,3-dipolar cycloaddition reactions with aliphatic and aromatic nitriles, alkenes, alkynes, phenylisothiocyanate and carbon disulphide. In all cases the products have been isolated in high yield. From extensive kinetic studies the following order of reactions have been noted, alkynes > nitriles >> alkenes. The activation of azido group is dependent upon the nature of associated ligand L ; the reaction rate decreases with the increase of α-donor capacity of L. Palladium(II) complexes are less active than the nickel(II) analogues because of decreased charge density of the metal ion. The rate constants of cycloaddition reactions increase with reactants carrying electron withdrawing group, and in the case of aromatic nitriles Hammett correlationship has been obtained. The mechanism of reaction has been discussed in the light of thermodynamic parameters of activated state.