title: A Family of Chiral Ferrocenyl Diols: Modular Synthesis, Solid-State Characterization, and Application in Asymmetric Organocatalysis.
abstract: Readily available chiral diol scaffolds are useful as sources of chirality for asymmetric synthesis, however, few such scaffolds are readily available in enantiopure form. Reported herein is a cheap and modular synthesis of a novel family of chiral ferrocenyl diols in excellent yields with excellent enantio- and diastereoselectivity (>99 % ee and 99 % de). These diols possess not only planar and central chirality, but also axial chirality around the central iron atom. Characterization of these diols by X-ray crystallography revealed intra- and intermolecular hydrogen-bond networks depending on substitution at the carbinol positions. The potential of these diols as catalysts was subsequently demonstrated in an asymmetric hetero-Diels-Alder reaction which provided cycloadducts in up to 84 % yield with ee values ranging from -92 to +72 %.
authors.affiliation: Centre for Synthesis and Chemical Biology, School of Chemistry, University College Dublin, Belfield, Dublin 4, Ireland.
authors.forename: Chris
authors.initials: C
authors.lastname: Nottingham
authors.affiliation: Centre for Synthesis and Chemical Biology, School of Chemistry, University College Dublin, Belfield, Dublin 4, Ireland.
authors.forename: Helge
authors.initials: H
authors.lastname: Müller-Bunz
authors.affiliation: Centre for Synthesis and Chemical Biology, School of Chemistry, University College Dublin, Belfield, Dublin 4, Ireland. p.guiry@ucd.ie.
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Guiry
keywords: chirality; cycloaddition; diols; organocatalysis; planar chirality