Ferrocene derivatives, LXXI; Stereochemistry of metallocenes, LVI Synthesis and structure of optically active ferrocenylaminoalcohols

The reaction of enantiomerically pure 1,2-(-N,N-dimethylamino)-tetramethylene ferrocene (4) with butyllithium and subsequent treatment with either benzophenone or paraformaldehyde has yielded the aminoalcohols 6–11. The absolute configurations of 4 and 6–11 were deduced from the X-ray structures of the (R,R)-tartrate of 4 (4-T) and the aminoalcohol 6. In addition the optical purity of 4 was shown to be at least 95% by transformation into the ketone 2. In solution the annelated six-membered ring in compounds 4 and 6–11 was found to adopt a preferred half-chair conformation very similar to that found in the solid state structures of 4-T and 6.