Die Reaktionen vontBu2P-P=P(Me)tBu2 und (Me3Si)tBuP-P=P(Me)tBu2 mit PR3

Abstract

Ad memoriam Egon WibergInhaltsu È bersicht. t Bu 2 P±P=P(Me) t Bu 2 (1) reagiert bei 20°C mit PMe 3 , PEt 3 , P(c-Hex) 3 , P(p-Tol) 3 , PPh 2 Me, PPh 2 Et, PPhEt 2 , PPh 2 i Pr, PPh 3 und P(NEt 2 ) 3 unter Bildung von t Bu 2 P±P=PR 3 und t Bu 2 PMe. P t Bu 3 , P t Bu 2 (SiMe 3 ) und t Bu 2 PCl reagieren nicht mit 1. t Bu 2 PH bildet mit 1 t Bu 2 P±PH±P t Bu 2 , das in der Reaktionslo È sung mit PEt 3 zum t Bu 2 P±P=PEt 3 reagiert. Ph 2 PH, t BuPH 2 , PH 3 , Ph 2 PCl und EtOH substituieren nicht die t Bu 2 PMe-Gruppe von 1, sondern spalten das Moleku È l. (Me 3 Si) t BuP±P=P(Me) t Bu 2 bildet mit PEt 3 das (Me 3 Si) t BuP±P=PEt 3 . Die Verbindungen t Bu 2 P±P=PR 3 zersetzen sich bei 20°C in unterschiedlichem Maûe zu P-reichen Folgeprodukten des Phosphinophosphinidens. Bu 2 PH and 1 form t Bu 2 P±PH±P t Bu 2 which yields t Bu 2 P±P=PEt 3 when treated with PEt 3 . Ph 2 PH, t BuPH 2 , PH 3 , Ph 2 PCl and EtOH don't substitute the t Bu 2 PMe group in 1, instead, the molecule is decomposed. With PEt 3 , (Me 3 Si) t BuP±P=P(Me) t Bu 2 forms (Me 3 Si) t BuP±P=PEt 3 . The compounds t Bu 2 P±P=PR 3 decompose at 20°C to different degrees giving P-rich consecutive products of the phosphinophosphinidene.

Bonding in Phosphanylphosphinidene Complexes of Transition Metals and their Correlation with Structures, 31P NMR Spectra, and Reactivities

“…In the presence of alkenes, t Bu 2 P–P forms phosphiranes. Even more explicitly, the electrophilic properties of t Bu 2 P–P are visible in a transphosphination reaction (Scheme ). An examination of the equilibrium in these reactions clearly indicates that adducts t Bu 2 P–P=PR 3 , having more nucleophilic phosphines PR 3 , predominate in the solution.…”

“…The main points addressed in this work are: finding driving factors behind different types of coordination; determining what affects the shortening of the P–P and P–M bonds; and describing the impact of the type of metal on the nucleophilicity and electrophilicity of the considered complexes. Additionally, structural, spectral, and chemical properties of Bertrand's free phosphanylphosphinidene, are compared with the structural and spectral properties of t Bu 2 P–P (DFT calculations) and the chemical properties of its PR 3 complex, t Bu 2 P–P=P t Bu 2 (Me) , , . Furthermore, we compare the calculated properties of Frank's putative phosphanylphosphinidene Me 2 Si(µ 2 ‐NR) 2 P–P, which reveals an unusual dimerization mode …”

Reactions of Lithium Salts of Triphosphanes tBu2P–PLi–PtBu2 and tBu2P–PLi–P(NEt2)2 with Metal Complexes [(R3P)2MCl2] (M = Ni, Pd, Pt, R3P = Et3P, pTol3P, Ph2EtP, iPr3P)

“…The reaction of [(Et 3 P) 2 PtCl 2 ] with t Bu 2 P–P(SiMe 3 )–P t Bu 2 (run 4.2) yielded significant amounts of ( t Bu 2 P) 3 P. However, we did not detect fairly stable [(η 2 ‐ t Bu 2 P=P)Pt(PEt 3 ) 2 ], but t Bu 2 P–P=PEt 3 24. Moreover, ( t Bu 2 P) 3 P was isolated after the reaction of [(Et 2 PhP) 2 PtCl 2 ] with t Bu 2 P–PLi–P(NEt 2 ) 2 · 2THF.…”

“…31 P NMR spectroscopic examination of the reaction solution (101.26 MHz, C 6 D 6 , THF, 25 °C): ( t Bu 2 P) 3 P 23, [ cis ‐(Et 3 P)( t Bu 2 PH)PtCl 2 ], t Bu 2 PH, p Tol 3 P, [ cis ‐(Et 3 P) 2 PtCl 2 ], [ trans ‐(Et 3 P) 2 PtCl 2 ], t Bu 2 P–P=PEt 3 24.…”

Coordination‐Like Chemistry of Phosphinidenes by Phosphanes

“…Importantly, these phosphanylphosphanylidenephosphoranes also undergo phosphane‐exchange reactions (Scheme ) to provide access to other phosphanylphosphanylidenephosphoranes 14,15. The position of the equilibrium reactions varied as the nature of the PR′ 3 groups changed.…”