(Ethane-1,2-di­yl)bis­[bis­(3-methoxy­prop­yl)methyl­phospho­nium] bis­(tetra­phenyl­borate) diethyl ether solvate

In the course of substitution studies on the iron dihydrogen complex trans-[Fe(DMeOPrPE)(2)(H(2))H](BPh(4)) {DMeOPrPE = 1,2-bis­[bis­(methoxy­prop­yl)phosphino]ethane}, we discovered an unexpected transformation of the diphosphine ligand to a diphospho­nium dication without the use of any typical methyl­ating reagent. The P atoms in the dication of the title compound, C(20)H(46)O(4)P(2) (2+)·2C(24)H(20)B(−)·C(4)H(10)O, have a distorted tetra­hedral coordination with P—C(Me) distances of 1.791 (2) and 1.785 (2) Å. The P—C—C—P torsion angle about the central dimethyl­ene bridge is −168.3 (1)°.