Metal Amine Carboxylates as Hydronium Ion Traps. Part 5.1. The Structure of K_1/2(H₅O₂)_1/2{(−)_D-trans-(O₆)-[Co(1,3-SS-pddadp)]}· 2H₂O (I) Determined at 18°C and −100°C and of Li{(−)_D-trans-(O₆)-[Co(1,3-SS-pddadp)]}·7H₂O (II) AT 18°C. Intra- and Intermolecular Interactions in the Crystallization of Metal Diamine Carboxylates and on Hydronium Ion Traps

Abstract

Optically pure (I), CoK_0.5O₁₁N₂C₁₃H_24.5, crystallizes in the orthorhombic system, space group P2₁2₁2, in acell whose characteristics, at 18°C, area = 16.614(2), b = 12.250(2) and c = 9.068(2) Ä; V = 1845.4 ij, d(calc, z = 4,M.W. = 433.865g mol⁻¹) = 1.561 g cm⁻³. At −100°C, the cell constants are: a = 16.555(2), b = 12.161(2), c = 9.027(3) Ä; V = 1817.28, d(z = 4,M.W. = 433.865 g mol⁻¹) = 1.694 g cm⁻³. For the 18°C set, a total of 2564 data were collected in the range 4° ≤ 20 ≤ 55° which were corrected for LP factors and absorption effects (psi scans, μ = 6.630 cm⁻¹; rel. trans. coeff. range from 0.9446 to 0.9999); of these, 1562 were unique and had I ≥ 3σ(I) and were used throughout the calculations described. The absolute configuration was determined from refinements of the solution (+ + +) and inverted configuration (−−−). During the test, the R(F) and R _W (F) indices were, respectively, (+ + +)= 0.0473 and 0.0618 and (−−−) = 0.0525 and 0.0644. The final R(F) and R _W (F) values were, respectively, 0.0443 and 0.0527. The same crystal, on the same goniometer head, was used for low temperature data collection, which refined to final R(F) and R _W (F) values of 0.0644 and 0.0756. Coordinates from the absolute determination at 18°C were used as trial coordinates for the low temperature data set, which refined immediately. It is interesting to note that, initially, the salt was prepared as the pure potassium salt but that upon purification (Dowex50 column, chloride form) the salt was isolated as the double potassium-hydronium derivative. The compound, as a racemate, crystallizes as racemic crystals in the monoclinic system (P2₁/c) and does not form the hydronium salt (see ref. 20).

Optically pure (II), LiCoO₁₅N₂C₁₃H₃₂, crystallizes in the orthorhombic system, space group P2₁2₁2₁,in a cell whose edges are a = 7.361 (3), b = 3.150(2) and c = 22.503(2) Ä; V = 2178.18 ij, d(calc.,z = 4,M.W. = 522.28 g mol⁻¹) = 1.593 g cm⁻³. A total of 3015 data were collected in the range 4° ≤ 20 ≤ 56° which were corrected for LP factors and absorption effects (psi scans, μ = 8.574 cm⁻¹; rel. trans. coeff. range from 0.9570 to 0.9980); of these, 1628 were unique and had I ≥ 3σ(I) and were used throughout the calculations described. The absolute configuration was determined from refinements of the solution (+ + +) and inverted configuration (−−−). During the test, the R(F) and R _W (F) indices were, respectively, (+ + +) = 0.0443 and 0.0491 and (−−−) = 0.0524 and 0.0553. The final R(F) and R _W (F) values were, respectively, 0.0399 and 0.0453. As a racemate, the compound crystallizes as a racemate in the triclinic space group PĪ (unpublished results, see ref. 21).

We were interested in observing the mode of crystallization as a function of changes in the length of the methylene chains in the amine and carboxylato fragments. In the effect on packing by changing the charge compensating cations (do they cause changes in the mode of crystallization; e.g., racemic to conglomerate?). And, also, in establishing the absolute configuration of the anions in order to correlate this information to the spectrochemical data (CD) of the anions. Upon realizing that they would not crystallize as conglomerates, we were forced to use pre-resolved ligands to prepare the anions.

On Leave from the Technical University of Wroclaw, I-5, Wroclaw, Poland