No abstract

No abstract

No abstract

No abstract

The potassium bis-dithiocarbamate (bis-dtc) salts of 1,3-bis(benzylaminomethyl)benzene (1,3-Bn-ambdtc), 1,3-bis(iso-butylaminomethyl)benzene (1,3-(i)Bu-ambdtc), 1,4-bis(benzylaminomethyl)benzene (1,4-Bn-ambdtc), and 1,4-bis(iso-butylaminomethyl)benzene (1,4-(i)Bu-ambdtc) were reacted with three different diorganotin dichlorides (R2SnCl2 with R = Me, (n)Bu, and Ph) in 1:1 stoichiometric ratios to give the corresponding diorganotin bis-dithiocarbamates. Additionally, the dimethyltin bis-dithiocarbamate of 1,1'-bis(benzylaminomethyl)ferrocene (1,1'-Bn-amfdtc) was prepared. The resulting complexes have been characterized as far as possible by elemental analysis, FAB(+) mass spectrometry, IR and NMR ((1)H, (13)C, and (119)Sn) spectroscopy, and single-crystal X-ray diffraction, showing that the tin complexes are dinuclear 24- and 26-membered macrocyclic species of composition [{R2Sn(bis-dtc)}2]. As shown by (119)Sn NMR spectroscopy, the tin centers are hexa-coordinated in all cases; however, two different coordination environments are possible, as detected by single-crystal X-ray diffraction. In the dimethyltin derivatives of 1,3-Bn-ambdtc, 1,3-(i)Bu-ambdtc, 1,4-Bn-ambdtc, and 1,1'-Bn-amfdtc and the di-n-butyltin derivative of 1,3-(i)Bu-ambdtc, the metal atoms are embedded in skewed-trapezoidal-bipyramidal coordination polyhedra with asymmetrically coordinating trans-oriented dtc groups. In contrast, in the diphenyltin derivative 1,3-(i)Bu-ambdtc, the metal centers have distorted octahedral coordination with symmetrically coordinating cis-oriented dtc functions. Thus, for the complexes derived from 1,3-Bn/(i)Bu-ambdtc, two different macrocyclic structures were observed. In the dimethyl- and di-n-butyltin derivatives, the bridging bis-dtc ligands adopt U-shaped conformations, while in the case of the diphenyltin derivative, the conformation is L-shaped. Furthermore, two different macrocyclic ring conformations can occur, which differ in the spatial orientation of the substituents attached to the nitrogen atoms (Bn or (i)Bu). The dimethyltin derivatives of 1,4-Bn-ambdtc and 1,1'-Bn-amfdtc have cavities, in which aromatic rings are accommodated in the solid state.

Racemic trinuclear diphenyltin(IV) cavitands and capsules have been assembled from diphenyltin(IV) and tris-dithiocarbamate ligands.

Seven dinuclear macrocyclic palladium(II) dithiocarbamates have been prepared from a homologous series of aliphatic 1,x‐diamines (x = 4–10); the objective was to vary systematically the size of the cavity. The resulting complexes were characterized by IR and NMR (1H, 13C) spectroscopy, high‐resolution FAB mass spectrometry, and in one case additionally by single‐crystal X‐ray diffraction analysis. Geometry‐optimizations using the B3LYP functional in combination with the def2‐SVP basis set were performed for the complete series of 22‐ to 36‐membered macrocycles and showed that these can be divided into two classes. Palladium(II) dithiocarbamates with an even number of methylene spacer groups yield macrocycles of rectangular shape with overall dimensions that vary from 6.0 × 14.5 × 12.7 to 6.0 × 15.7 × 19.9 Å3, whereas an odd number generates hexagon‐shaped assemblies with overall dimensions in the range 5.0 × 16.3 × 13.0 to 6.0 × 21.1 × 18.7 Å3. The computational analysis ruled out the possibility that monomeric structures had formed and indicated that for the creation of strain‐free mononuclear macrocyclic structures at least 14 methylene groups are required in the spacer.

No abstract