Aminophobanes: hydrolytic stability, tautomerism and application in Cr-catalysed ethene oligomerisation. Issue 5 (18th January 2016)

• Record Type: Journal Article
• Authors: Haddow, Mairi F.; Jaltai, Judit; Hanton, Martin; Pringle, Paul G.; Rush, Laura E.; Sparkes, Hazel A.; Woodall, Christopher H.
• Is Part Of: Dalton transactions. Volume 45:Issue 5(2016)
• Page Start: 2294
• Page End: 2307
• Publication Date: 2016-01-18
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/c5dt04394h
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : The bicyclic aminophobanes have significantly different chemistry from their acyclic analogues Cy2 PNHR′. Abstract : 9-Amino-9-phosphabicyclo[3.3.1]nonanes, (PhobPNHR′; R = Me or i Pr) are readily prepared by aminolysis of PhobPCl and are significantly less susceptible to hydrolysis than the acyclic analogues Cy2 PNHR′. Treatment of Cy2 PNHMe with Cy2 PCl readily gave Cy2 PNMePCy2 . By contrast, treatment of PhobPCl with PhobPNHMe in the presence of Et3 N does not afford PhobPNMePPhob but instead the salt [PhobP(NMeH)PPhob]Cl is formed which, upon addition of [PtCl2 (NC t Bu)2 ] gives the zwitterionic complex [PtCl3 (PhobP(NMeH)PPhob)]. The neutral PhobP(NMe)PPhob is accessible from PhobNMeLi and is converted to the chelate [PdCl2 (PhobPNMePPhob)] by addition of [PdCl2 (cod)]. The anomalous preference of the PhobP group for the formation of PPN products is discussed. The unsymmetrical diphos ligands PhobPNMePAr2 (Ar = Ph, o -Tol) are prepared, converted to [Cr(CO)4 (PhobPNMePAr2 )] and shown to form Cr-catalysts for ethene oligomerisation, producing a pattern of higher alkenes that corresponds to a Schulz-Flory distribution overlaid on selective tri/tetramerisation.