Summary: | We describe the synthesis of planar-chiral diferrocene compounds <b>4</b>, <b>7</b> and <b>12,</b> intended as key precursors for a new family of asymmetric catalyst ligands with less complex structures than their popular equivalents. In contrast to conventional 1,2-disubstituted ferrocenes containing center-chiral and planar-chiral elements, these compounds are purely planar-chiral due to the absence of α-substiuted ethyl groups. The title compounds <b>4</b>, <b>7</b> and <b>12</b> were obtained from known precursors in 87%, 59% and 60% yields, respectively.
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