Jerry P. Jasinski tribute
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A cuboidal [Cu4(SO4)4] structure supported by β-picoline ligands
aPortsmouth Abbey School, 285 Cory's Lane, Portsmouth, RI, 02871, USA, and bUniversity of Massachusetts Dartmouth, 285 Old Westport Road, North Dartmouth, MA 02747, USA
*Correspondence e-mail: dmanke@umassd.edu
The solid-state structure of the cobalt–β-picoline–sulfate complex tetra-μ3-sulfato-tetrakis[bis(3-methylpyridine)cobalt(II)], [Co4(SO4)4(C6H7N)8], is reported. The tetrameric cobalt cluster contains a cuboidal core comprised of four cobalt(II) cations and four sulfate anions at alternate cube vertices. The cobalt corners are each capped with two β-picoline ligands. The sulfate anions adopt a rare [3.2110] bridging motif, and the cuboidal cluster is unprecedented in coordination chemistry.
Keywords: crystal structure; picoline; sulfate; transition metal; coordination chemistry; cobalt complexes.
CCDC reference: 2143864
1. Chemical context
For the past few years, our lab has examined the solid-state structures of first-row transition-metal–pyridine–sulfate complexes (Park et al., 2019; Pham et al., 2018; Roy et al., 2018). Despite the first such compound being reported in 1886 (Jørgensen, 1886; Manke, 2021), the structures of only two had been described in the literature when we started exploring this class of compounds. A series of these structures including Fe, Co, Ni, and Zn, showed one-dimensional coordination polymers exhibiting sulfate dianions bridging in μ-sulfato-κ2O:O′ modes. Interestingly, by modifying growth conditions, cobalt demonstrated two additional crystalline forms with variation in the bridging mode of sulfate ions that was not observed for the other metals. We have also explored the structural chemistry of such complexes with substituted pyridines, including γ-picoline, which showed similar structural chemistry to that observed with the pyridine ligand (Pham et al., 2019). When we looked at the reaction of cobalt sulfate with β-picoline, a unique structure was obtained, a tetramer exhibiting an unprecedented cuboidal Cu4(SO4)4 core, described herein.
2. Structural commentary
The β-picoline ligands (Fig. 1). When grown out, the cobalt center demonstrates a pseudo-octahedral coordination environment. This consists of two β-picoline nitrogen atoms, two oxygen atoms of a chelating sulfate ligand, one oxygen atom of a second sulfate anion, which bridges to another metal, and one terminal oxygen atom of a third sulfate ligand. The grown-out structure forms a tetramer of (β-pic)2CoSO4 units, demonstrating a cuboidal core in which four vertices are occupied by cobalt cations, and the other four vertices are occupied by sulfate anions (Fig. 2). The sulfate anions all bridge three Co2+ cations, demonstrating [3.2110] bridging by Harris notation (Fig. 3). Harris notation is written as [X·YYYY] where X is the number of metals that a ligand bridges, and the Ys are the number of metals connected to each donor atom in the ligand (Papatriantafyllopoulou et al., 2009). The [3.2110] bridging motif is rare in sulfates and has only been observed in 1D coordination polymers of copper (Li et al., 2008) and lanthanide/iron mixed-metal 3D coordination polymers (He et al., 2017). There are two C—H⋯O interactions between the ortho hydrogens of one β-picoline ligand and the oxygens of two sulfate ions (Table 1). This results in a plane-to-plane angle between the CoN3O plane and the pyridine ring of 16.25 (9)°. These interactions are not present in the second unique picoline ligand, giving a larger plane-to-plane angle of 26.95 (9)°.
of the title compound contains one cobalt cation, one sulfate anion, and two3. Supramolecular features
The crystal packing for the compound is shown in Fig. 4. The are weak C—H⋯O interactions between the trans-hydrogen atom of one picoline ligand and one of the terminal sulfate oxygens of a neighboring cuboid [C3—H3⋯O2ii; symmetry code: (ii) + x, − y, − z, Table 1). This interaction might assist in the interdigitation of the cuboids in the structure. No significant π–π interactions are observed.
4. Database survey
The reported structures demonstrating sulfate ions with [3.2110] bridging modes are with copper (DOHKIV, DOHKIB: Li et al., 2008) or mixtures of lanthanides with iron (He et al., 2017), including dysprosium (DADNOO), erbium (DADPEG), europium (DADNII), gadolinium (DADNUU) and samarium (DADPAC). The prior structures of metal–pyridine sulfate complexes include three variations with pyridine (QIBFOZ: Pham et al., 2018; QOXJAR, QOXJEV: Park et al., 2019) and one with γ-picoline (ROFMIL: Pham et al., 2019), all of which demonstrate 1D coordination polymers that are structurally quite different than the cuboidal compound reported here.
5. Synthesis and crystallization
32 mg of CoSO4·7H2O were dissolved in 2.0 mL of 3-methylpyridine (Aldrich) and heated at 343 K for 24 h. Dark-pink crystals suitable for X-ray analysis were obtained.
6. Refinement
Crystal data, data collection and structure . Hydrogen atoms were placed in calculated positions [C—H = 0.93 Å (sp2) and 0.96 Å (sp3)]. Isotropic displacement parameters were set to 1.2UeqC (sp2) or 1.5UeqC (sp3).
details are summarized in Table 2Supporting information
CCDC reference: 2143864
https://doi.org/10.1107/S2056989022000780/zl5027sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989022000780/zl5027Isup2.hkl
Data collection: APEX3 (Bruker, 2018); cell
SAINT (Bruker, 2018); data reduction: SAINT (Bruker, 2018); program(s) used to solve structure: SHELXT2014 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015b); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: publCIF (Westrip, 2010).[Co4(SO4)4(C6H7N)8] | Dx = 1.571 Mg m−3 |
Mr = 1364.96 | Mo Kα radiation, λ = 0.71073 Å |
Tetragonal, P421c | Cell parameters from 9496 reflections |
a = 15.6121 (16) Å | θ = 2.9–25.7° |
c = 11.8359 (13) Å | µ = 1.35 mm−1 |
V = 2884.9 (7) Å3 | T = 298 K |
Z = 2 | BLOCK, pink |
F(000) = 1400 | 0.24 × 0.22 × 0.20 mm |
Bruker D8 Venture CMOS diffractometer | 2624 reflections with I > 2σ(I) |
φ and ω scans | Rint = 0.037 |
Absorption correction: multi-scan (SADABS; Bruker, 2018) | θmax = 25.7°, θmin = 2.9° |
Tmin = 0.517, Tmax = 0.562 | h = −19→19 |
54595 measured reflections | k = −19→19 |
2744 independent reflections | l = −14→14 |
Refinement on F2 | H-atom parameters constrained |
Least-squares matrix: full | w = 1/[σ2(Fo2) + (0.0165P)2 + 1.2064P] where P = (Fo2 + 2Fc2)/3 |
R[F2 > 2σ(F2)] = 0.019 | (Δ/σ)max = 0.001 |
wR(F2) = 0.046 | Δρmax = 0.16 e Å−3 |
S = 1.14 | Δρmin = −0.20 e Å−3 |
2744 reflections | Extinction correction: SHELXL-2018/3 (Sheldrick 2015b), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
184 parameters | Extinction coefficient: 0.0049 (4) |
0 restraints | Absolute structure: Flack x determined using 1117 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013) |
Hydrogen site location: inferred from neighbouring sites | Absolute structure parameter: 0.007 (4) |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
Co1 | 0.64636 (2) | 0.49053 (2) | 0.41389 (3) | 0.02066 (11) | |
S1 | 0.52522 (4) | 0.64004 (4) | 0.35520 (5) | 0.02043 (15) | |
O1 | 0.58168 (12) | 0.57205 (12) | 0.30908 (15) | 0.0267 (4) | |
O2 | 0.49144 (15) | 0.69145 (13) | 0.26473 (17) | 0.0370 (5) | |
O3 | 0.45605 (11) | 0.59894 (11) | 0.42553 (16) | 0.0240 (4) | |
O4 | 0.57304 (12) | 0.69234 (11) | 0.43961 (15) | 0.0258 (4) | |
N1 | 0.75982 (14) | 0.57112 (15) | 0.4121 (2) | 0.0319 (5) | |
N2 | 0.70169 (16) | 0.42286 (15) | 0.2775 (2) | 0.0293 (5) | |
C1 | 0.82170 (19) | 0.5691 (2) | 0.4896 (3) | 0.0400 (7) | |
H1 | 0.813680 | 0.534627 | 0.552786 | 0.048* | |
C2 | 0.8976 (2) | 0.6156 (2) | 0.4819 (3) | 0.0489 (8) | |
C3 | 0.9084 (2) | 0.6660 (2) | 0.3863 (3) | 0.0546 (10) | |
H3 | 0.958296 | 0.697697 | 0.376688 | 0.065* | |
C4 | 0.8451 (2) | 0.6690 (2) | 0.3064 (3) | 0.0541 (10) | |
H4 | 0.851466 | 0.702977 | 0.242445 | 0.065* | |
C5 | 0.7719 (2) | 0.6210 (2) | 0.3218 (3) | 0.0434 (8) | |
H5 | 0.729157 | 0.623471 | 0.267110 | 0.052* | |
C6 | 0.9650 (3) | 0.6110 (3) | 0.5724 (4) | 0.0829 (15) | |
H6A | 0.946445 | 0.572676 | 0.630913 | 0.124* | |
H6B | 0.973938 | 0.667009 | 0.603611 | 0.124* | |
H6C | 1.017567 | 0.590328 | 0.540358 | 0.124* | |
C7 | 0.6638 (2) | 0.4183 (2) | 0.1768 (3) | 0.0340 (7) | |
H7 | 0.611734 | 0.446338 | 0.167140 | 0.041* | |
C8 | 0.6978 (2) | 0.3738 (2) | 0.0853 (3) | 0.0422 (7) | |
C9 | 0.7741 (2) | 0.3311 (2) | 0.1032 (3) | 0.0499 (9) | |
H9 | 0.798504 | 0.299413 | 0.045000 | 0.060* | |
C10 | 0.8143 (2) | 0.3351 (2) | 0.2062 (3) | 0.0490 (9) | |
H10 | 0.865907 | 0.306837 | 0.218114 | 0.059* | |
C11 | 0.7766 (2) | 0.3817 (2) | 0.2914 (3) | 0.0386 (8) | |
H11 | 0.803962 | 0.384829 | 0.361126 | 0.046* | |
C12 | 0.6512 (3) | 0.3707 (3) | −0.0255 (3) | 0.0732 (12) | |
H12A | 0.590895 | 0.377919 | −0.012705 | 0.110* | |
H12B | 0.661205 | 0.316328 | −0.061099 | 0.110* | |
H12C | 0.671634 | 0.415746 | −0.073630 | 0.110* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Co1 | 0.01998 (17) | 0.02203 (18) | 0.01997 (16) | 0.00207 (14) | 0.00180 (15) | 0.00176 (14) |
S1 | 0.0216 (3) | 0.0201 (3) | 0.0196 (3) | 0.0031 (3) | 0.0031 (2) | 0.0046 (3) |
O1 | 0.0293 (10) | 0.0290 (10) | 0.0218 (9) | 0.0075 (8) | 0.0056 (8) | 0.0029 (8) |
O2 | 0.0435 (12) | 0.0380 (11) | 0.0297 (10) | 0.0114 (11) | −0.0007 (10) | 0.0133 (9) |
O3 | 0.0227 (9) | 0.0272 (9) | 0.0223 (9) | −0.0037 (7) | 0.0042 (8) | 0.0004 (8) |
O4 | 0.0259 (9) | 0.0213 (9) | 0.0301 (11) | −0.0045 (8) | 0.0048 (8) | 0.0015 (7) |
N1 | 0.0281 (12) | 0.0299 (12) | 0.0378 (13) | −0.0040 (10) | 0.0080 (12) | 0.0009 (12) |
N2 | 0.0305 (12) | 0.0272 (12) | 0.0301 (13) | 0.0033 (11) | 0.0070 (11) | 0.0008 (11) |
C1 | 0.0349 (16) | 0.0417 (17) | 0.0434 (18) | −0.0091 (14) | 0.0040 (14) | 0.0014 (14) |
C2 | 0.0337 (16) | 0.051 (2) | 0.062 (2) | −0.0128 (14) | 0.0054 (17) | −0.0051 (19) |
C3 | 0.0408 (19) | 0.043 (2) | 0.080 (3) | −0.0156 (16) | 0.0191 (18) | 0.0026 (18) |
C4 | 0.052 (2) | 0.042 (2) | 0.068 (3) | −0.0086 (16) | 0.019 (2) | 0.0151 (18) |
C5 | 0.0396 (18) | 0.0437 (19) | 0.0470 (19) | −0.0036 (15) | 0.0103 (16) | 0.0107 (16) |
C6 | 0.048 (2) | 0.102 (4) | 0.098 (4) | −0.026 (2) | −0.017 (3) | 0.002 (3) |
C7 | 0.0376 (17) | 0.0333 (15) | 0.0310 (15) | −0.0005 (13) | 0.0067 (13) | 0.0015 (13) |
C8 | 0.061 (2) | 0.0340 (16) | 0.0314 (15) | −0.0070 (14) | 0.0115 (17) | −0.0043 (14) |
C9 | 0.067 (2) | 0.0349 (17) | 0.048 (2) | 0.0039 (16) | 0.0277 (18) | −0.0072 (15) |
C10 | 0.047 (2) | 0.0364 (18) | 0.063 (2) | 0.0135 (15) | 0.0187 (18) | −0.0001 (16) |
C11 | 0.0369 (18) | 0.0342 (17) | 0.045 (2) | 0.0085 (14) | 0.0064 (14) | 0.0007 (14) |
C12 | 0.107 (4) | 0.076 (3) | 0.036 (2) | −0.002 (3) | −0.002 (3) | −0.012 (2) |
Co1—S1i | 2.7458 (7) | C3—C4 | 1.368 (6) |
Co1—O1 | 2.0441 (19) | C4—H4 | 0.9300 |
Co1—O3i | 2.2037 (19) | C4—C5 | 1.379 (5) |
Co1—O3ii | 2.1274 (18) | C5—H5 | 0.9300 |
Co1—O4i | 2.1229 (18) | C6—H6A | 0.9600 |
Co1—N1 | 2.173 (2) | C6—H6B | 0.9600 |
Co1—N2 | 2.114 (2) | C6—H6C | 0.9600 |
S1—O1 | 1.4839 (19) | C7—H7 | 0.9300 |
S1—O2 | 1.438 (2) | C7—C8 | 1.391 (4) |
S1—O3 | 1.5069 (18) | C8—C9 | 1.382 (5) |
S1—O4 | 1.491 (2) | C8—C12 | 1.501 (5) |
N1—C1 | 1.332 (4) | C9—H9 | 0.9300 |
N1—C5 | 1.336 (4) | C9—C10 | 1.371 (6) |
N2—C7 | 1.333 (4) | C10—H10 | 0.9300 |
N2—C11 | 1.345 (4) | C10—C11 | 1.376 (5) |
C1—H1 | 0.9300 | C11—H11 | 0.9300 |
C1—C2 | 1.392 (4) | C12—H12A | 0.9600 |
C2—C3 | 1.389 (5) | C12—H12B | 0.9600 |
C2—C6 | 1.503 (5) | C12—H12C | 0.9600 |
C3—H3 | 0.9300 | ||
O1—Co1—S1i | 129.94 (5) | N1—C1—H1 | 118.0 |
O1—Co1—O3ii | 94.41 (7) | N1—C1—C2 | 124.0 (3) |
O1—Co1—O3i | 97.00 (7) | C2—C1—H1 | 118.0 |
O1—Co1—O4i | 162.52 (7) | C1—C2—C6 | 121.6 (4) |
O1—Co1—N1 | 92.08 (9) | C3—C2—C1 | 116.9 (3) |
O1—Co1—N2 | 92.84 (9) | C3—C2—C6 | 121.5 (3) |
O3i—Co1—S1i | 33.21 (5) | C2—C3—H3 | 120.2 |
O3ii—Co1—S1i | 81.36 (5) | C4—C3—C2 | 119.7 (3) |
O3ii—Co1—O3i | 86.57 (8) | C4—C3—H3 | 120.2 |
O3ii—Co1—N1 | 173.44 (9) | C3—C4—H4 | 120.4 |
O4i—Co1—S1i | 32.58 (5) | C3—C4—C5 | 119.3 (3) |
O4i—Co1—O3ii | 83.94 (7) | C5—C4—H4 | 120.4 |
O4i—Co1—O3i | 65.55 (7) | N1—C5—C4 | 122.6 (4) |
O4i—Co1—N1 | 90.16 (9) | N1—C5—H5 | 118.7 |
N1—Co1—S1i | 95.20 (8) | C4—C5—H5 | 118.7 |
N1—Co1—O3i | 93.61 (8) | C2—C6—H6A | 109.5 |
N2—Co1—S1i | 136.90 (7) | C2—C6—H6B | 109.5 |
N2—Co1—O3i | 170.11 (9) | C2—C6—H6C | 109.5 |
N2—Co1—O3ii | 91.63 (8) | H6A—C6—H6B | 109.5 |
N2—Co1—O4i | 104.59 (8) | H6A—C6—H6C | 109.5 |
N2—Co1—N1 | 87.07 (9) | H6B—C6—H6C | 109.5 |
O1—S1—Co1iii | 116.43 (7) | N2—C7—H7 | 118.2 |
O1—S1—O3 | 108.92 (10) | N2—C7—C8 | 123.6 (3) |
O1—S1—O4 | 109.93 (11) | C8—C7—H7 | 118.2 |
O2—S1—Co1iii | 133.48 (9) | C7—C8—C12 | 120.8 (3) |
O2—S1—O1 | 110.07 (11) | C9—C8—C7 | 116.8 (3) |
O2—S1—O3 | 112.71 (12) | C9—C8—C12 | 122.4 (3) |
O2—S1—O4 | 112.15 (12) | C8—C9—H9 | 119.7 |
O3—S1—Co1iii | 53.22 (7) | C10—C9—C8 | 120.6 (3) |
O4—S1—Co1iii | 50.06 (7) | C10—C9—H9 | 119.7 |
O4—S1—O3 | 102.82 (11) | C9—C10—H10 | 120.6 |
S1—O1—Co1 | 121.04 (10) | C9—C10—C11 | 118.7 (3) |
Co1ii—O3—Co1iii | 124.11 (9) | C11—C10—H10 | 120.6 |
S1—O3—Co1ii | 141.48 (12) | N2—C11—C10 | 122.3 (3) |
S1—O3—Co1iii | 93.57 (9) | N2—C11—H11 | 118.9 |
S1—O4—Co1iii | 97.36 (9) | C10—C11—H11 | 118.9 |
C1—N1—Co1 | 124.8 (2) | C8—C12—H12A | 109.5 |
C1—N1—C5 | 117.5 (3) | C8—C12—H12B | 109.5 |
C5—N1—Co1 | 117.4 (2) | C8—C12—H12C | 109.5 |
C7—N2—Co1 | 121.9 (2) | H12A—C12—H12B | 109.5 |
C7—N2—C11 | 118.1 (3) | H12A—C12—H12C | 109.5 |
C11—N2—Co1 | 120.0 (2) | H12B—C12—H12C | 109.5 |
Co1iii—S1—O1—Co1 | −1.75 (15) | O4—S1—O3—Co1iii | −7.25 (10) |
Co1iii—S1—O3—Co1ii | −168.6 (2) | N1—C1—C2—C3 | −0.5 (5) |
Co1—N1—C1—C2 | 173.9 (3) | N1—C1—C2—C6 | 179.7 (4) |
Co1—N1—C5—C4 | −174.0 (3) | N2—C7—C8—C9 | 1.5 (5) |
Co1—N2—C7—C8 | −179.4 (2) | N2—C7—C8—C12 | 179.5 (3) |
Co1—N2—C11—C10 | 178.4 (2) | C1—N1—C5—C4 | 0.4 (5) |
O1—S1—O3—Co1iii | 109.34 (9) | C1—C2—C3—C4 | 0.8 (5) |
O1—S1—O3—Co1ii | −59.3 (2) | C2—C3—C4—C5 | −0.6 (6) |
O1—S1—O4—Co1iii | −108.29 (10) | C3—C4—C5—N1 | −0.1 (6) |
O2—S1—O1—Co1 | 176.64 (13) | C5—N1—C1—C2 | −0.1 (5) |
O2—S1—O3—Co1iii | −128.20 (11) | C6—C2—C3—C4 | −179.4 (4) |
O2—S1—O3—Co1ii | 63.1 (2) | C7—N2—C11—C10 | −0.6 (4) |
O2—S1—O4—Co1iii | 128.92 (11) | C7—C8—C9—C10 | −1.5 (5) |
O3—S1—O1—Co1 | −59.31 (15) | C8—C9—C10—C11 | 0.6 (5) |
O3—S1—O4—Co1iii | 7.57 (11) | C9—C10—C11—N2 | 0.5 (5) |
O4—S1—O1—Co1 | 52.63 (15) | C11—N2—C7—C8 | −0.5 (4) |
O4—S1—O3—Co1ii | −175.90 (17) | C12—C8—C9—C10 | −179.4 (3) |
Symmetry codes: (i) y, −x+1, −z+1; (ii) −x+1, −y+1, z; (iii) −y+1, x, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
C1—H1···O4i | 0.93 | 2.53 | 3.116 (4) | 121 |
C3—H3···O2iv | 0.93 | 2.46 | 3.135 (4) | 129 |
C5—H5···O1 | 0.93 | 2.49 | 3.070 (4) | 121 |
Symmetry codes: (i) y, −x+1, −z+1; (iv) x+1/2, −y+3/2, −z+1/2. |
Funding information
Funding for this research was provided by: National Science Foundation, Directorate for Mathematical and Physical Sciences (grant No. CHE-1429086).
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