Abstract: | Tetrakis(chloromethyl)phosphonium chloride monohydrate, C4H8Cl4P+·Cl?·H2O or P(CH2Cl)4+·Cl?·H2O, is the first crystal structure determination of a tetrakis(halogenomethyl)phosphonium compound to date. The only comparable structures known so far are of phosphonium ions containing just one halogenomethyl group. The solvent water molecule interacts with the Cl? anion via hydrogen bonds, with O?Cl distances of 3.230 (2) and 3.309 (2) Å. The structure also contains several C—H?Cl? and C—H?O contacts, though with longer D?A distances [D?A 3.286 (3)–3.662 (2) Å] or bent D—H?A angles. For these reasons, the C—H?Cl? and C—H?O interactions should not be considered as strong hydrogen bonds. |