Organoetallic chemistry of the transition metals XXVII. Some new rhodium complexes of allene pentamer (1,2,5,6,8-pentamethyenecyclodecane)

Abstract

Several reactions of rhodium(I) complexes of 1,2,5,6,8-pentamethylenecyclodecane (allene pentamer, C 15H 20) are described. Reaction of the chloride C 15H 20RhCl with (pentafluorophenyl)lithium in diethyl ether gives the yellow crystalline σ-pentafluorophenyl derivative C 15H 20RhC 6F 5, apparently the first known example of a derivative with a transition metalcarbon σ-bond where all of the other ligands are coordinated carboncarbon double bonds. Reaction of C 15H 20RhCl with sodium cyclopentadienide in tetrahydrofuran solution gives yellow waxy C 15H 20RhC 5H 5 shown by its NMR spectrum to have a tetrahapto-1,2,5,6,8-pentamethylenecyclodecane ligand and a pentahapto-cyclopentadienyl ligand. The predominant ion in the mass spectrum of C 15H 20RhC 5H 5 is C 15H 20Rh + which is formed by loss of C 5H 5 from the molecular ion. Reaction of C 15H 20RhCl with stannous chloride in diethyl ether gives yellow C 15H 20RhSnCl 3. Reaction of C 15H 20RhCl with silver hexafluorophosphate in acetone solution gives the yellow salt [C 15H 20Rh][PF 6]. This salt reacts with carbon monoxide at atmospheric pressure to give the yellow monocarbonyl [C 15H 20RhCO][PF 6], which can also be obtained by reaction of C 15H 20RhCl with carbon monoxide in boiling ethanol followed by reaction with ammonium hexafuorophosphate in aqueous acetone.