Ethane-1,2-diphosphonic acid as a building block in supramolecular chemistry; a pillared-layer framework and framework-encapsulated cations

Abstract

The 1:1 adduct of piperazine and ethane-1,2-diphosphonic acid is a salt [C(4)H(12)N(2)](2+).[C(2)H(6)O(6)P(2)](2-), in which both ions lie across centres of inversion in space group P2(1)/c. The anions are linked by a single type of O-H...O hydrogen bond [O...O, 2.562 (3) A; H...O, 1.73 A, O-H...O, 169 degrees ] into (6, 3) nets built from a single type of R(4)(4)(22) ring. The cations lie between these nets, linked to them by two types of N-H...O hydrogen bond [N...O, 2.635 (3) and 2.735 (3) A; H...O 1.72 and 1.82 A, N-H...O, 175 and 177 degrees ] such that the cations link adjacent sheets, thus forming a pillared-layer framework. The aquated adduct formed between trimethylenedipiperidine and ethane-1,2-diphosphonic acid is also a salt [C(13)H(28)N(2)](2+).[C(2)H(6)O(6)P(2)](2-).2.8[H(2)O], in which there are 12 different types of hydrogen bond, eight O-H...O and four N-H...O. The anions are linked into chains by pairs of O-H...O hydrogen bonds and these chains are linked by the water molecules into a continuous three-dimensional framework. Within the anion/water framework are large voids which contain pairs of cations, linked to the framework by N-H...O hydrogen bonds.

Cobalt Phosphonates: An Unusual Polymeric Cobalt Phosphonate Containing a Clathrated Phosphonate Anion and a Layered Bisphosphonate

“…In the adduct anionic diphosphonic ligands are linked together and with the corresponding cations by hydrogen bonding. It should be noted that the bond distances and angles in C−PO 3 moieties of the adduct are very close to those observed in the compound [Co(H 2 O) 4 (H 4 L)][H 2 L]·2H 2 O (Table ), even though no metal is involved in the adduct …”

“…Such an arrangement results in the formation of a one-dimensional framework in which the clathrated uncoordinated ligand H 2 L acts as a counterion to the positively charged [Co(H 2 O) 4 (H 4 L)] 2+ motif. Similar behavior of diphosphonic acids has been observed in the 1:1 adduct of piperazine and 1,2-ethylenediphosphonic acid [C 4 H 12 N 2 ] 2+ [HO 3 P(CH 2 ) 2 PO 3 H] 2- . In the adduct anionic diphosphonic ligands are linked together and with the corresponding cations by hydrogen bonding.…”

“…In the literature alkyldiphosphonic acids are well-known as a precursor of self-assembled monolayers (SAMs) and multilayer films on high surface area silica and gold surfaces. , In addition diphosphonic acids can be employed as building blocks in supramolecular chemistry. Thus, the acid with two members in alkyl chains forms hydrogen-bonded adducts with a pillar-layered framework .…”

A comparative structural study of alkane- α,ω-diphosphonic acids

“…The strategy of using diphosphonic acids as tectons for the construction of void-containing metal phosphonates has been introduced by Dines et al as early as 1983 [32]. In the context of crystal engineering, alkane-α,ω-diphosphonic acids have also been used to design new materials building up one-, two-and three-dimensional coordination polymeric networks [33][34][35][36][37][38][39][40]. Former investigations of chemical and physical properties of alkane-α,ω-diphosphonic acids, H 2 O 3 P-(CH 2 ) n -PO 3 H 2 with n = 1-6 and 10 [41,42], have shown remarkable changes of measured melting points, IR spectra and NMR spectra as n increases.…”

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

“…34 However, organic salts of organophosphonic acids, e.g. with primary, [35][36][37][38][39] secondary [40][41][42] and tertiary 39,[43][44][45][46][47][48] amines, seem to be feasible model compounds for metal phosphonates as they exhibit similar structural characteristics and are less complicated to crystallise. A common feature of the synthesis of these materials in solution is the transfer of a proton from the phosphonic acid to the amine.…”