Asymmetric Synthesis of Planar Chiral 2-Monosubstituted Diferrocenyl Ketones

Abstract

A highly efficient and rapid entry to planar chiral 2-monosubstituted diferrocenyl ketones is reported. Key step is the highly diastereoselective ortho-metalation of diferrocenyl ketone-SAMP-hydrazone, followed by trapping with various electrophiles. The subsequent racemisation-free cleavage of the chiral auxiliary affords the title diferrocenyl ketones 4a-g with one exception in good to very good overall yields and all with high enantiomeric excesses (ee = 97-99%).

Key words

asymmetric synthesis - ortho-metalation - hydrazones - diferrocenyl ketones - planar chirality

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