ISSN:
0009-2940
Keywords:
Cobaltocenes, highly substituted
;
Cyclopentadienyl ligand, sterically demanding
;
Ferrocenes, highly substituted
;
Hindered rotation of ring ligands
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Complexes with Sterically Demanding Ligands, V. - Synthesis of 4-tert-Butyl-1,2-bis(trimethylsilyl) cyclopentadienyl Complexes of Iron and Cobalt2-tert-Butyl-5,5-bis(trimethylsilyl)-2,4-cyclopentadiene (1) is prepared in a one-pot synthesis starting from 1,1-dimethylfulvene. Deprotonation of 1 with n-butyllithium yields the lithium derivative Li[C5H2(CMe3)(SiMe3)2] (2) which is treated with FeBr2· DME and CO to cleanly give [C5H2(CMe3)(SiMe3)2]Fe(CO)2Br (3). Ferrocene and cobaltocenium cation derivatives [C5H2-(CMe3)(SiMe3)2]2M (M = Fe: 4; M = Co⊕ PF6⊖: 5) have also been synthesized using 2. Variable-temperature 1H-NMR spectroscopy shows that rotation of the five-membered ring about the metal-ring axis is hindered in these metallocenes.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19891220612
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