Pyridyl‐Functionalized 1‐Phosphabarrelene: Synthesis, Coordination Chemistry and Photochemical di‐π‐Methane Rearrangement. Issue 63 (1st October 2019)

• Record Type: Journal Article
• Authors: Bruce, Marlene; Papke, Martin; Ehlers, Andreas W.; Weber, Manuela; Lentz, Dieter; Mézailles, Nicolas; Slootweg, J. Chris; Müller, Christian
• Is Part Of: Chemistry. Volume 25:Issue 63(2019)
• Page Start: 14332
• Page End: 14340
• Publication Date: 2019-10-01
• Subjects: coordination chemistry -- DFT calculations -- di-pi-methane rearrangement -- phosphabarrelene -- phosphorus ligands; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201903344
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: The [4+2] cycloaddition of 2‐(2′‐pyridyl)‐4, 6‐diphenyl‐λ 3 ‐phosphinine with the highly reactive dienophile hexafluoro‐2‐butyne has been studied and the first pyridyl‐functionalized 1‐phosphabarrelene was obtained and structurally characterized. Although monodentate CF3 ‐1‐phosphabarrelenes show only a poor coordination ability, the chelating nature of the novel P, N‐hybrid ligand gives access to various transition‐metal complexes. Upon irradiation with UV light, the pyridyl‐functionalized 1‐phosphabarrelene undergoes a rather selective di‐π‐methane rearrangement in the coordination sphere of the metal center, leading to the formation of a complex based on a hitherto unknown pyridyl‐functionalized 5‐phosphasemibullvalene derivative. DFT calculations provide first insights into the mechanism of this reaction. Abstract : Do a barrel roll ! A detailed study on the synthesis, coordination chemistry, and reactivity of a novel bis‐CF3 ‐substituted, pyridyl‐functionalized 1‐phosphabarrelene is presented. Upon irradiation with UV light, a chelating 5‐phosphasemibullvalene is formed by a rather selective di‐π‐methane rearrangement of the 1‐phosphabarrelene P, N‐ligand in the coordination sphere of a metal center.