Chloride−Chloroform Clusters Exhibiting Weak Hydrogen and Halogen Bondings Are Fully Characterized in the Solid State by X-ray Diffraction

Abstract

Two (1,3,5-triazapentadiene/ato)PtII complexes, [1][(Cl)2] and [2][(Cl)2], were synthesized by the previously reported platinum-mediated nitrile−amidine coupling. Both complexes crystallize as mixed chloroform−ethanol solvate [1][(Cl)2(CHCl3)7(EtOH)2] and [2][(Cl)2(CHCl3)6(EtOH)2] from the reaction mixture by slow evaporation of the commercial chloroform (containing ca. 1% of EtOH) taken as the solvent, while crystals of [2][(Cl)2(CHCl3)4] were obtained when distilled chloroform was employed. In the crystal structure of [1][(Cl)2(CHCl3)7(EtOH)2], [2][(Cl)2(CHCl3)6(EtOH)2], and [2][(Cl)2(CHCl3)4] solvates, the Cl− ion interacts with [1]2+ or [2]2+ by means of hydrogen bonding and via one hydrogen bridge, thus forming stacked arrays. The negatively charged cluster ions [Cl−(CHCl3) n ] (n = 2, 3) are stabilized via C−H···Cl− hydrogen bridges between the Cl− ion and CHCl3 molecules. In [1][(Cl)2(CHCl3)7(EtOH)2], two chloroform clusters dimerize to the [Cl−(CHCl3)3]2 species, where the halogen bonding between one Cl atom of CHCl3 and Cl− anion was detected. The halogen bonding was studied by theoretical methods (B3LYP, MP2), including the bond energy, AIM, and NBO charge transfer analyzes.

A family of heterotetrameric clusters of chloride species and halomethanes held by two halogen and two hydrogen bonds

“…Firstly, we report here on a new family of heterotetrameric clusters held by simultaneous two C-X•••Cl XB's and two C-H•••Cl HB's with halomethanes. This family has now been extended from a single associate of CHCl 3 with uncomplexed Cl -(previously reported by us 26 ) to a large set of heterotetramers incorporating (i) not only CHCl 3 , but also rather weak XB/HB donors such as CH 2 Cl 2 and CH 2 Br 2 , (ii) neutral chloride platinum(II) complexes, where XB/HB-accepting chloride is bound to a platinum center, and (iii) organic molecules, RCl, acting as simultaneous XB/HB donors and XB/HB acceptors. Secondly, our theoretical calculations indicate that the XB's and HB's in the reported clusters are cooperative.…”

“…Only one cluster in structure UPEROX was described in our previous work. 26 Other structures. Dibromomethane was so rarely studied as XB donor and only the H 2 BrC-Br•••Br, 58 ]dodecan-5-one (structure KAVDUG, Figure 10).…”

“…The M06 functional is much less time-consuming than the MP2 method used by us previously,26,67 at the same time, the M06 functional describes reasonably weak dispersion forces and non-covalent interactions 68,69. No symmetry operations have been applied.…”

Diiodomethane as a halogen bond donor toward metal-bound halides

“…1) are still able to form supramolecular clusters with chloride anions and chloride ligands in metal complexes held by XBs and HBs 16,21,22 or by simultaneous XB and HB. 16,21,22 In contrast to a rather broad application of halomethanes in crystal engineering, diiodomethane (CH 2 I 2 ) -despite its relatively large σ-holes ( Fig. 1; positive potential is up to 23.1 kcal mol −1 on the 0.001 a.u.…”

Platinum(II)‐Mediated Double Coupling of 2,3‐Diphenylmaleimidine with Nitrile Functionalities To Give Annulated Pentaazanonatetraenate (PANT) Systems

“…[8][9][10][11] Metal- [12][13][14][15][16][17][18] or boron-containing [18] TAPDs exhibit luminescence properties and they also serve as components of catalytic systems. [19,20] In addition, as we recently established by combined X-ray crystallographic and theoretical methods, metal-TAPD complexes are useful for studies of weak molecular interactions, such as hydrogen [21][22][23][24] and halogen bonding, [21,24] or clustering [21][22][23] in the solid state.…”