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Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Disentangling Norrish-type and Rh catalysed decomposition of aldehydes for use as CO donors
Jasmin Hack1, Alina Schmitt1, Maik Seemann1
1Technische Universität Ilmenau, Institute of Chemistry and Bioengineering, Group of Physical Chemistry/Catalysis, Weimarer Str. 32, 98693 Ilmenau, Germany. robert.geitner@tu-ilmenau.de.
Abstract:
This study presents a detailed mechanistic investigation of the photocatalytic decomposition of different aldehydes via various Norrish reaction pathways and their subsequent role in the carbonylation of hydrocarbons, particularly toluene, using [Rh(PMe3)2(Cl)(CO)] as a catalyst. Utilizing 1H NMR spectroscopy, we quantitatively analysed the kinetics of the reaction network, focusing on the formation of key products such as alkanes and alkenes. The results reveal multiple well-explainable structure-property relationships for different aldehyde structures. In addition, the presence of [Rh(PMe3)2(Cl)(CO)] significantly suppresses the decomposition rates, suggesting intersystem crossing between photoactivated aldehydes and the Rh complex, potentially reducing the aldehyde's excited state lifetime. Furthermore, we explored the structural characterization of Rh-phosphine complexes formed during the reaction, though the exact structures remain elusive.
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