Pg. Jones et A. Weinkauf, DIPHOSPHATRIPTYCENIUM CATIONS - STRUCTURES OF THE TRIFLATE SALTS OF P-METHYL-DIPHOSPHATRIPTYCENIUM AND P,P'-DIMETHYL-DIPHOSPHATRIPTYCENIUM, Zeitschrift fur Kristallographie, 209(1), 1994, pp. 68-70
The dication crystallises with imposed two-fold symmetry. Both cations
show P - C bonds appreciably shortened with respect to the parent com
pound 1,6-diphosphatriptycene. The cage C - C bonds are longer than th
e opposite bonds in the phenyl rings. The C (Ar) - P - C (Ar) angles w
iden by 6 - 7-degrees compared with the parent compound.