207571-69-5Relevant academic research and scientific papers
Chiral annulated cyclopentadienyl ligands: Synthesis and crystal structure of both exo and endo Rh{η5-Cp′}(cod)} [Cp′=(4S,7R)-1,2,3-triphenyl-4,8,8-trimethyl-1H,4,5,6,7-tetrahydro-4,7- methanoindenyl]
Ramsden, James A.,Milner, David J.,Adams, Harry,Bailey, Neil A.,Hempstead,White, Colin
, p. 355 - 366 (1998)
The title homochiral cyclopentadiene ligand C31H30 (i.e., Cp′H, 5) has been synthesised from camphor in four steps. The lithium salt of this ligand reacted with [Rh(cod)Cl]2 to give predominantly racemic (η4-cycloocta-1,5-diene)[η 5-1,2,3-triphenyl-4-methyl-7-isopropyl-1H-indenyl]rhodium although the desired RhCp′(cod) complex was formed in 20% yield as an equal mixture of endo 7a and exo 7b isomers. The X-ray structures of 7a and 7b have been determined at room temperature with use of Mo-Kα radiation (λ=0.71069 A). Both compounds crystallise in the orthorhombic space group P212121 (D24, No. 19); for compound 7a, a=13.549(23) A, b=14.490(25) A, c=15.909(14) A, V=3123(8) A3, Z=4 and Dc=1.303 g cm-3 and the structure was refined to R=0.0488 on the basis of 2545 independent reflections. For the exo isomer 7b, a=13.301(18) A, b=15.599(32) A, c=14.436(19) A, V=2995(10) A3, Z=4 and Dc=1.359 g cm-3; the structure was refined to R=0.0362 on the basis of 4620 independent reflections. Bromine reacts with the compounds 7a and 7b to give the corresponding [{Rh(Cp′)}2(μ-Br3)]Br3.
