title: Crystal structure of zwitterionic 2-[bis-(2-meth-oxy-phen-yl)phosphanium-yl]-4-methyl-benzene-sulfonate monohydrate di-chloro-methane monosolvate.
abstract: In the title compound, C21H21O5PS·H2O·CH2Cl2, the phospho-nium-sulfonate zwitterion has the acidic H atom located on the P atom rather than the sulfonate group. The S-O bond lengths [1.4453 (15)-1.4521 (14) Å] are essentially equal. In the crystal, the water mol-ecules bridge two zwitterions via Owater-H⋯Osulfonate hydrogen bonds into a centrosymmetric dimer. The dimers are further linked by weak CAr-yl-H⋯Osulfonate hydrogen bonds into chains extending along [100]. The PH(+) group is not involved in inter-molecular inter-actions.
authors.affiliation: Department of Chemistry, the University of Chicago, 5735 South Ellis ave, Chicago, IL 60637, USA.
authors.forename: Hongyang
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Chemistry, the University of Chicago, 5735 South Ellis ave, Chicago, IL 60637, USA.
authors.forename: Ge
authors.initials: G
authors.lastname: Feng
authors.affiliation: Department of Chemistry, the University of Chicago, 5735 South Ellis ave, Chicago, IL 60637, USA.
authors.forename: Alexander S
authors.initials: AS
authors.lastname: Filatov
authors.affiliation: Department of Chemistry, the University of Chicago, 5735 South Ellis ave, Chicago, IL 60637, USA.
authors.forename: Richard F
authors.initials: RF
authors.lastname: Jordan
keywords: crystal structure; hydrogen bonding; sulfonic acid; zwitterion