Neuartige basische Liganden für die homogenkatalytische Homologisierung von Methanol zu Ethanol, IV [1] Synthese, Eigenschaften und NMR-spektroskopische Untersuchungen von mehrzähnigen Furfurylphosphanen / Novel Basic Ligands for the Homogeneous Catalytic Homologation of Methanol to Ethanol, IV [1] Synthesis, Properties and NMR Spectroscopic Investigations on Polydentate Furfurylphosphanes

Abstract

The furfurylphosphonium salts [RP(CH₂C₄H₂O₃]Br (2a-c, e, f) [R = Ph (a). Mes (b). Me (c), t-Bu (e), CH₇C₄H₃O (f)] and [Ph₂P(CH₂C₄H₃O)₂]Br (6) are obtained by reaction of the silvlphosphanes RP(SiMe₃)₂ (1a-c, e). P(SiMe₃), (3) and Ph₂PSiMe₃ (5) with BrCH₂C₄H₃O (eq. (1). (2) and (5)). In THF 2a-c, e, f and 6 are degraded by LiAlH₄ to give the tri- and bidentate alkyl and aryl furfurylphosphanes RP(CH₂C₄H₃O)₂ (4a-c, e, f) and Ph₂PCH₂C₄H₃O (7). respectively (eq. (3) and (5)). The formation of EtP(CH₂C₄H₃O)₂ (4d) succeeds via degradation of the phosphonium salt [EtP(CH₂C₄H₃O)₃]I (2d) which results from the reaction of 4f and EtI (eq. (4)). From Ph₂PCI (8) and the Grignard compound ClMg(CH₂)₂C₄(CH₃)H₂O the bidentate P,O-ligand Ph₂P(CH₂)₂C₄(CH₃)H₂O (9) can also be isolated (eq.'(6)), ¹H, ³¹P{¹H}, and ¹³C{¹H} NMR spectroscopic investigations afford an insight into the structures of the novel compounds.