Regioselective Grafting of Two -CH2P(X)Ph2 Units (X = O, Lone Pair) onto a Resorcin[4]arene-Derived Cavitand

The first diphosphanes based on a resorcinarene‐derived cavitand were obtained in six steps starting from 5,11,17,23‐tetrabromo‐4(24),6(10),12(16),18(22)‐tetramethylenedioxy‐2,8,14,20‐tetrapentylresorcin[4]arene. The synthesis of these bulky ligands was based on the selective C‐2 functionalisation either of two proximal resorcinolic units or of two distal ones. The ligands, both of which were characterised by X‐ray diffraction, readily react with [RuCl2(p‐cymene)]2 to form the corresponding bimetallic complexes [RuCl2(p‐cymene)]2·L in which the cavitand shape remains unchanged with respect to that of the free phosphanes. The first diphosphanes based on a resorcinarene cavitand were conveniently prepared in six steps from a tetrabrominated precursor. The new ligands were shown tobe suitable for the preparation of bimetallic complexes without alteration of the shape of the generic cavitand core.