Synlett 2007(5): 0725-0728  
DOI: 10.1055/s-2007-970764
LETTER
© Georg Thieme Verlag Stuttgart · New York

A C 2-Symmetric Metallocene-Pyrrolidinopyridine Nucleophilic Catalyst for Asymmetric Synthesis

Huy V. Nguyen, Majid Motevalli, Christopher J. Richards*
School of Biological and Chemical Sciences, Queen Mary, University of London, Mile End Road, London E1 4NS, UK
Fax: +44(20)78827794; e-Mail: c.j.richards@qmul.ac.uk;
Further Information

Publication History

Received 12 January 2007
Publication Date:
08 March 2007 (online)

Abstract

A C 2-symmetric nucleophilic catalyst, (R,R)-3,5-diferrocenyl-4-(2′,5′-dimethylpyrrolidino)pyridine, was synthesised in three steps from commercially available (S,S)-hexane-2,5-diol. ­Application to the kinetic resolution of secondary alcohols (0.5 mol% loading) resulted in selectivity factors (s) of up to 6.

    References and Notes

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Nguyen, H. V.; Motevalli, M.; Richards, C. J. manuscript in preparation.

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Crystal data of 2.
C32H33Cl3Fe2N2, M = 663.65, orthorhombic, a = 7.3563(2), b = 17.9280(6), c = 21.8849(7) Å, α = 90°, β = 90°, γ = 90°, V = 2886.26(15) Å3, space group P212121, Z = 4, D c = 1.527 mg/m3, µ = 1.309 mm-1, reflections measured 21200, reflections unique 6560 with R int = 0.0495, T = 120 (2) K, final R indices [F2 >2σ(F2)] R1 = 0.0370, wR2 = 0.0670 and for all data R1 = 0.0457, wR2 = 0.0701 (CCDC 619938).