Tetrameric triphenylsilanol, (Ph3SiOH)(4), and the adduct (Ph3SiOH)(2)-dimethyl sulfoxide, both at 120 K, and the adduct (Ph3SiOH)(4)-1,4-dioxan at 150 K: interplay of O-H center dot center dot center dot O and C-H center dot center dot center dot pi(arene) interactions

The structure of tetrameric triphenylsilanol, C18H16OSi, (I), has been re-investigated at 120 (2) K. The hydroxyl H atoms were readily located and one of the arene rings is disordered over two closely positioned sets of sites. The molecules are linked into cyclic tetramers, having approximate (4) over bar (S-4) symmetry, via O-H...O hydrogen bonds [H...O 1.81- 1.85 Angstrom, O...O 2.634 (3)-2.693 (3) Angstrom and O-H...O 156- 166degrees]. At ambient temperature, there are indications of multiple disorder of the phenyl-ring sites. In bis(triphenylsilanol) dimethyl sulfoxide solvate, 2C(18)H(16)OSi.C2H6OS, (II), the dimethyl sulfoxide component is disordered across a twofold rotation axis in C2/c, and the molecular components are linked by a single O-H...O hydrogen bond [H...O 1.85 Angstrom, O...O 2.732 (2) Angstrom and O-H...O 172degrees] into three-molecule aggregates, which are themselves linked into a single three-dimensional framework by two C-H...pi (arene) interactions. In tetrakis(triphenylsilanol) 1,4-dioxan solvate, 4C(18)H(16)OSi.C4H8O2, (III), the 1,4-dioxan component lies across an inversion centre in space group P (1) over bar and centrosymmetric five-molecule aggregates are linked by paired CD H...pi(arene) interactions to form molecular ladders.