Molecular structures of 1,1′bis(diphenylphosphino) ferrocene oxide and sulphide and their thermal properties

Abstract

The crystal and molecular structure of anhydrous 1,1′-bis(diphenylphosphino) ferrocene sulphide, Fe[C5H4P(S)Ph2]2 (dppf S2), is reported and compared with the hydrated oxide analogue, Fe[C5H4P(O) Ph2]2 · 2H20 (dppfO2 · 2H20). It consists of two phosphoryl cyclopentadienyl rings [P-S = 1.938(2) Å] sandwiching an FeII centre. With four molecules per cell, the molecule is crystallographically required to sit on an inversion centre and hence the two rings are staggered. The thermal properties of [Fe(C5H4PPh2)2] (dppf), dppfO2 · 2H20 and dppfS2 were studied together with Fe(Cp)2 and Ph3PO · H2O by TGA and DSC. The thermal stability decreases in the order dppFO2 > dppf > dppf S2. The hydrogen-bonded hydrate in dppfO2 · 2H20 is removed upon heating to 110-160°C. © 1995.