Intermolecular insertion of dialkynylphosphanes into the M–C bond of cyclopalladated rings through activation by cyclometallated amines
A series of chiral ortho-platinated and -palladated complexes derived from N,N,α-trimethylbenzylamine has been prepared. The dialkynylphosphane PhP(C CMe)2 coordinated regiospecifically as a P M monodentate ligand to these cyclometallated units in the positions trans to the nitrogen donors of the...
| Main Authors: | , , , |
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| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2013
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| Online Access: | https://hdl.handle.net/10356/101892 http://hdl.handle.net/10220/11162 |
| Summary: | A series of chiral ortho-platinated and -palladated complexes
derived from N,N,α-trimethylbenzylamine has been prepared.
The dialkynylphosphane PhP(C CMe)2 coordinated
regiospecifically as a P M monodentate ligand to these cyclometallated units in the positions trans to the nitrogen donors of the metallacycles. Upon introduction of selected chirality on the benzylamine unit and subsequent monitoring by
using NMR spectroscopy, the P Pt bond was found to be
thermodynamically stable and kinetically inert. The P Pd
bond must be kinetically labile since the palladium complexes
readily undergo a facile ligand redistribution process. Nevertheless, both ortho-metallated units activated one of
the C C bonds towards an intermolecular Pd–C bond insertion
reaction into another cyclopalladated ring. No intramolecular
insertion reaction occurred within the same molecule.
Coordination of PhP(C CMe)2 to the ortho-palladated unit
also protected the organopalladium ring from intermolecular
attack by other coordinated dialkynylphosphanes. The Pt–C
bonds in cycloplatinated rings are not reactive toward the
insertion reaction, although they are good reaction activators
for coordinated dialkynylphosphanes. |
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