In:
Chemistry – A European Journal, Wiley, Vol. 26, No. 50 ( 2020-09-04), p. 11492-11502
Abstract:
Alkyne complexes with vicinal substitution by a Lewis acid and a Lewis base at the coordinated alkyne are prospective frustrated Lewis pairs exhibiting a particular mutual distance and, hence, a specific activation potential. In this contribution, investigations on the generation of a W II alkyne complex bearing a phosphine as Lewis base and a carbenium group as Lewis acid are presented. Independently on potential substrates added, an intramolecular cyclisation product was always isolated. A subsequent deprotonation step led to an unprecedented side‐on λ 5 ‐phosphinyne complex, which is interpreted as highly zwitterionic according to visible absorption spectroscopy supported by TD‐DFT. Low‐temperature 31 P NMR and EPR spectroscopic measurements combined with time‐dependent IR‐spectroscopic monitoring provided insights in the mechanism of the cyclisation reaction. Decomposition of the multicomponent IR spectra by multivariate curve resolution and a kinetic hard‐modelling approach allowed the derivation of kinetic parameters. Assignment of the individual IR spectra to potential intermediates was provided by DFT calculations.
Type of Medium:
Online Resource
ISSN:
0947-6539
,
1521-3765
DOI:
10.1002/chem.201905750
Language:
English
Publisher:
Wiley
Publication Date:
2020
detail.hit.zdb_id:
1478547-X
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