Back to Search
Start Over
Copper(ii) coordination polymers of imdc− (H2imdc+ = the 1,3-bis(carboxymethyl)imidazolium cation): unusual sheet interpenetration and an unexpected single crystal-to-single crystal transformation.
- Source :
- CrystEngComm; 2013, Vol. 15 Issue 45, p9729-9737, 9p
- Publication Year :
- 2013
-
Abstract
- The monoanion of 1,3-bis(carboxymethyl)imidazolium (H<subscript>2</subscript>imdc<superscript>+</superscript>) combines with Cu(ii) to produce an undulating 2D coordination polymer of composition [Cu<subscript>2</subscript>(imdc)<subscript>2</subscript>(CH<subscript>3</subscript>OH)<subscript>2</subscript>](BF<subscript>4</subscript>)<subscript>2</subscript>·(CH<subscript>3</subscript>OH)(H<subscript>2</subscript>O) (1) in which copper acetate-like dimers, linked by imdc<superscript>−</superscript> ligands, act as 4-connecting centres. Cationic sheets stack on top of each other in an A, B, A, B… fashion and produce a structure that contains channels running parallel to the plane of network. Tetrafluoroborate anions are located in channels between sheets. Upon removal of coordinated and non-coordinated solvent molecules a single crystal-to-single crystal transformation occurs to yield a similar compound but with BF<subscript>4</subscript><superscript>−</superscript> anions now coordinated. CO<subscript>2</subscript> isotherms measured at 258 and 273 K show only modest uptake of CO<subscript>2</subscript> but provide an indication that the sheets move apart at elevated pressures in order to accommodate the guest molecules. A compound of composition [Cu<subscript>3</subscript>(OH)<subscript>2</subscript>(imdc)<subscript>2</subscript>]·SiF<subscript>6</subscript>·2H<subscript>2</subscript>O·2MeOH (3), which possesses a 3D network, is formed by the combination of copper(ii) acetate, copper(ii) hexafluorosilicate and Himdc. In this structure infinite parallel Cu<subscript>3</subscript>(OH)<subscript>2</subscript> chains are linked by bridging imdc<superscript>−</superscript> ligands to form channels that have an approximately triangular cross-section. These channels are occupied by SiF<subscript>6</subscript><superscript>2−</superscript> anions in addition to solvent molecules. When copper(ii) acetate is combined with Himdc in the appropriate ratio, a 1D coordination polymer of composition Cu(imdc)<subscript>2</subscript> (4) is formed in which pairs of imdc<superscript>−</superscript> anions bridge Cu(ii) centres. When the reaction is performed in the presence of NaBF<subscript>4</subscript> a minor crystalline product with tetragonal symmetry is isolated in addition to the 1D coordination polymer. This compound of composition Cu<subscript>2</subscript>(imdc)<subscript>4</subscript>NaBF<subscript>4</subscript>·7H<subscript>2</subscript>O (5) consists of 2D Cu(imdc)<subscript>2</subscript> networks and features an unusual mode of interpenetration. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 14668033
- Volume :
- 15
- Issue :
- 45
- Database :
- Complementary Index
- Journal :
- CrystEngComm
- Publication Type :
- Academic Journal
- Accession number :
- 100892428
- Full Text :
- https://doi.org/10.1039/c3ce41226a