Crystal Structure of the First Polymeric Tetramercurated Methane Derivative of Hofmann's Base

By dissolving Hofmann's base, [CHg^sub 4^O(OH^sub 2^)](OH)^sub 2^ - a polymeric organomercury compound, in trifluoromethanesulfonic acid, crystals of [CHg^sub 4^(OH)(OH^sub 2^)^sub 2^](CF^sub 3^SO^sub 3^)^sub 3^ . 2H^sub 2^O were obtained and characterized by X-ray diffraction. It is the first polymeric tetramercurated methane derivative of Hofmann's base. The asymmetric unit of the monoclinic P2^sub 1^/n space group consists of a monomeric unit of the polymeric cation [CHg^sub 4^(OH)(OH^sub 2^)^sub 2^]^sup 3n+^^sub n^, three trifluoromethanesulfonate anions and two crystallization water molecules. In the polymeric chains two neighbouring tetramercurated methane moieties are interconnected through an OH group - a dimercurated oxonium ion, -Hg-(OH)^sup +^-Hg-. H2O molecules are bound to two mercury atoms that do not take part in the bridging and represent monomercurated oxonium ions -HgOH^sup +^^sub 2^. The polymeric chains are arranged in parallel puckered layers and are interlinked by an extensive three-dimensional hydrogen-bonding network. The characteristic coordination of mercury atoms is linear, while the effective coordination is 2+3. [PUBLICATION ABSTRACT]