title: Adducts of hexamethylenetetramine with ferrocenecarboxylic acid and ferrocene-1,1'-dicarboxylic acid: multiple disorder in space groups Fmm2 and Cmcm.
abstract: Hexamethylenetetramine, C(6)H(12)N(4), and ferrocenecarboxylic acid, C(11)H(10)FeO(2), form a 1:2 adduct, (I), which is a salt, viz. hexamethylenetetraminium(2+) bis(ferrocenecarboxylate), (C(6)H(14)N(4))[Fe(C(5)H(5))(C(6)H(4)O(2))](2). The dication in (I) is disordered with two orientations at a site of mm2 symmetry in space group Fmm2, while the anion lies across a mirror plane with its unsubstituted cyclopentadienyl ring disordered over two sets of sites. With ferrocene-1,1'-dicarboxylic acid, C(12)H(10)FeO(4), hexamethylenetetramine forms a 1:1 adduct, (II), in which both components are neutral, viz. hexamethylenetetramine-ferrocene-1,1'-dicarboxylic acid (1/1), [Fe(C(6)H(5)O(2))(2)].C(6)H(12)N(4). The amine component in (II) is disordered with two orientations at a site of mm2 symmetry in space group Cmcm, while the acid component is disordered with two orientations at a site of 2/m symmetry. The components in (I) are linked into a finite three-ion aggregate by a single N-H.O hydrogen bond, while the components of (II) are linked into continuous chains by a single O-H.N hydrogen bond.
authors.affiliation: School of Chemistry, University of St Andrews, St Andrews, Fife KY16 9ST, Scotland.
authors.forename: Choudhury M
authors.initials: CM
authors.lastname: Zakaria
authors.forename: George
authors.initials: G
authors.lastname: Ferguson
authors.forename: Alan J
authors.initials: AJ
authors.lastname: Lough
authors.forename: Christopher
authors.initials: C
authors.lastname: Glidewell