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Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Bis(2,4,7-trimethylindenyl)cobalt(II) and rac-2,2',4,4',7,7'-hexamethyl-1,1'-biindene
O Stenzel1, M W Esterhuysen, H G Raubenheimer
1Department of Chemistry, Stellenbosch University, Private Bag X1, Matieland 7600, South Africa.
Abstract:
The crystal and molecular structures of bis(eta(5)-2,4,7-trimethylindenyl)cobalt(II), [Co(C(12)H(13))(2)], (I), and rac-2,2',4,4',7,7'-hexamethyl-1,1'-biindene, C(24)H(26), (II), are reported. In the crystal structure of (I), the Co atom lies on an inversion centre and the structure represents the first example of a bis(indenyl)cobalt complex exhibiting an eclipsed indenyl conformation. The (1R,1'R) and (1S,1'S) enantiomers of the three possible stereoisomers of (II), which form as by-products in the synthesis of (I), cocrystallize in the monoclinic space group P2(1)/c. In the unit cell of (II), alternating (1R,1'R) and (1S,1'S) enantiomers pack in non-bonded rows along the a axis, with the planes of the indenyl groups parallel to each other and separated by 3.62 and 3.69 A.
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