Abstract
An optimised synthesis of 1,1′-bis (2-indenyl)ferrocene in
47% yield from the Pd(0)-catalysed cross coupling between
1,1′-zincated ferrocene and 2-bromo-indene is described
along with the formation of (2-indenyl) ferrocene in 40% yield.
The analogous synthesis of planar chiral derivatives gave either
pure N ,N -dimethyl-1-[2-(2-indenyl)ferrocenyl]ethylamine
(74%) or N ,N -dimethyl-1-[2,1′-bis (2-indenyl)ferrocenyl]ethylamine
(26%) dependent upon the amount of Pd(0) catalyst used.
Key words
ferrocene carbanions - coupling - metallocene
ligands
References
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mg, 5.37 mmol) in THF (25 mL) at 0 °C. The resulting
orange slurry was warmed to r.t. and stirred for 1 h. In a separate
Schlenk flask DIBAL (0.54 mL of a 1.0 M soln in hexanes, 0.54 mmol)
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40%); The spectral data were identical to the literature (ref.
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2
),
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Hz, Cp-H ), 4.43 (4 H, t, J = 1.8 Hz,
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NMR (62.9 MHz, CDCl3 ): δ = 39.7, 67.7,
70.2, 82.2, 119.9, 123.4, 123.7, 124.6, 126.5, 142.5, 145.1, 145.7.
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