A detailed comparative structural study of the hydrogen bonded networks in solids, obtained by the reaction of 4,4′-bipyridine and varied alkane-α,ω-diphosphonic acids

Abstract

In a comparative structural study, the solid state structures of seven new compounds obtained by the reaction of 4,4′-bipyridine and alkane-α,ω-diphosphonic acids with different chain lengths have been characterised by single crystal X-ray diffraction and vibrational spectroscopy. The compounds are composed of either [4,4′-Hbipy] + or [4,4′-H 2 bipy] 2+ cations and [H 2 O 3 P(CH 2) n PO 3 H] − anions and exhibit layered structures with clearly separated anionic and cationic areas. Within the three [4,4′-Hbipy] + salts, the 4,4′bipyridin-1-ium cations are connected to adjacent ones by medium strong, charge supported N +-H⋯N hydrogen bonds to form infinite chains. The anionic substructures of these compounds are quite different. The crystal structures of the five [4,4′-H 2 bipy] 2+ salts consist of anionic, hydrogen bonded strands which are linked to adjacent ones by 4,4′-bipyridine-1,1′-diium cations. All but one can be broken down into two different types of structures in which the cations either lie in line with the anionic strands (type 1) or perpendicular to the aforementioned (type 2). For [4,4′-H 2 bipy][H 2 O 3 P(CH 2) 6 PO 3 H] 2 (2), two concomitant polymorphs have been obtained and characterised by single crystal and powder X-ray diffraction. Both polymorphs were classifiable into type 1 and 2, respectively. Only [4,4′-H 2 bipy][H 2 O 3 P(CH 2) 9 PO 3 H] 2 (4) is a three-dimensional hydrogen bonded framework and therefore not assignable to one of these two types of structures. π-System distances and a remarkable bending of the alkylene chains document the contribution of π-π-stacking and van der Waals interactions to the lattice enthalpy.

Hydrogen bonds and van der Waals forces as tools for the construction of a herringbone pattern in the crystal structure of hexane-1,6-diaminium hexane-1,6-diyl bis(hydrogen phosphonate)

“…An additional, often neglected feature of such IR spectra are the broad bands associated with the O-H stretching vibration indicating strong hydrogen bonds (Hadži, 1965;Baran et al, 1989). A detailed discussion has also been reported very recently (van Megen et al, 2016a) for this feature. In the IR spectrum of the title compound, the maxima of the so called A, B and C bands can be estimated to be at 2750, 2200 and 1600 cm À1 .…”

“…(2004);Fuller & Heimer (1995);Glidewell et al (2000);Kan & Ma (2011);Mahmoudkhani & Langer (2002a,b,c);Plabst et al (2009); vanMegen et al (2016a,b);Wheatley et al (2001).For related hexane-1,6-diaminium salts, see: Assaf & Nau (2015); Boncel et al (2014); Bujoli-Doeuff et al (2012);Blerk & Kruger (2008);Frank & Reiss (1997);Holtby et al (2007);Wilkinson & Harrison (2007); vanMegen et al (2015).For closely related hydrogen-bonded compounds with a herringbone pattern, see:Thalladi et al (2000); vanMegen et al (2016a).…”

Crystal structure of 4-(4′-(pyridin-4-yl)-[1,1′-biphenyl]-4-yl)pyridin-1-ium 2-carboxy-4-(3,5-dicarboxyphenoxy)benzoate hydrate, C38H28N2O10

“…The bond lengths and angles are in the expected ranges. The monocation donates and accepts hydrogen bonds [8]. The same is true for the anion and together with the water molecule a hydrogen-bonded network is created.…”

Hydrogen bonding, π–π stacking and van der Waals forces-dominated layered regions in the crystal structure of 4-aminopyridinium hydrogen (9-phosphonononyl)phosphonate

“…Mostly, these organic solids establish extended hydrogenbonded networks which are characterized by a rich diversity of strong charge-supported hydrogen bonds (Aakerö y & Seddon, 1993) and can either be one-, two-or three-dimensional. This contribution forms part of our research on the principles of the arrangement of alkane-,!-diphosphonic acids (van Megen et al, 2015) and their organic aminium salts (van Megen et al, 2016). Moreover, aminopyridines and the related protonated cations are of crucial interest in the field of biochemistry (Muñ oz-Caro & Niñ o, 2002;Bolliger et al, 2011) and are also used as counter-cations to stabilize complex salts (Reiss & Leske, 2014a,b), in crystal engineering (Sertucha et al, 1998; Surbella III et al, 2016) as well as in polymer chemistry (Deng et al, 2015).…”