Synthesis, Molecular Structure, and Catalytic Evaluation of Centrostereogenic Ferrocenophane Phosphines

1,1′-[(1R)-1-Diarylphosphino-1,3-propanediyl]­ferrocenes,
where aryl = phenyl, 2-tolyl, 4-tolyl, mesityl, 4-anisyl, 4-(trifluoromethyl)­phenyl,
were prepared as new chiral ferrocenophane phosphines featuring only
central chirality in good yields by the reaction of the corresponding
chiral alcohol, 1,1′-[(1R)-1-hydroxy-1,3-propanediyl]­ferrocene,
and diarylphosphines in the presence of chlorotrimethylsilane and
sodium iodide. These phosphines were studied as ligands in palladium­(II)
complexes and further evaluated in two mechanistically different model
catalytic reactions, namely in Pd-catalyzed asymmetric allylic alkylation
of 1,3-diphenylallyl acetate with dimethyl malonate, and in enantioselective
aza-Morita-Baylis-Hillman reactions of aromatic N-sulfonyl imines with methyl vinyl ketone.