Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270100001104/qa0215sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270100001104/qa0215Isup2.hkl |
CCDC reference: 142935
The title compound was prepared by the reaction of N-methylpyrrolidinone (0.99 g, 0.96 ml, 20 mmol) with freshly sublimed dibromodimethylstannane (3.09 g, 10 mmol) derived from the reaction of dimethyltin oxide with HBr (Pfeiffer, 1902) in 10 ml of dry diethyl ether. The reaction mixture is stirred for 30 min and afterwards stored in a refrigerator at 278 K. Colourless crystals are obtained in quantitative yield after filtration and drying in vacuo, m.p. 315 K. A solution of the complex (80 mg) in C6D6 (410 mg) gives the following values for the structure-relevant NMR parameters: 2J(119Sn-13C-1H) = 77 Hz, 1J(119Sn-13C) = 561 Hz and δ(119Sn) = −34.8 p.p.m. These values represent an equilibrium between complexed and uncomplexed dimethyltin dibromide molecules, which is as expected shifted when the pure complex is studied at 325 K: 2J(119Sn-13C-1H) = 83 Hz, 1J(119Sn-13C) = 637 Hz, δ(119Sn) = −95.8 p.p.m.. The structure-relevant FT–IR data are as follows (neat, CsBr plates): ν (cm−1) = 2982 (vw, νC—H), 2928 (vw, νC—H), 2897 (vw, νC—H), 1637 (versus, νC=O), 562 (w, νSn—C), 514 (w, νSn—C), 222 (s, νSn—Br), 211 (m, νSn—Br) (McDermott, 1986; Matsubayashi et al., 1968).
The data collections covered the whole sphere of reciprocal space. The crystal to detector distance was 3.5 cm. Crystal decay was monitored by repeating the initial frames at the end of data collection. Analysing the duplicate reflections there were no indications for any decay. The structures were solved by direct methods (Sheldrick, 1990) and successive difference Fourier syntheses. Refinement applied full-matrix least-squares methods (Sheldrick, 1997). All H atoms were placed in calculated positions and refined with a riding model (including free rotation about C—C bonds), and with Uiso constrained to be 1.5Ueq of the carrier atom.
Data collection: Nonius KappaCCD software; cell refinement: DENZO and SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997) and PARST95 (Nardelli, 1995).
[SnBr2(CH3)2(C5H9NO)] | F(000) = 768 |
Mr = 407.71 | Dx = 2.214 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71069 Å |
a = 10.652 (1) Å | Cell parameters from 9229 reflections |
b = 7.002 (1) Å | θ = 2.5–27.1° |
c = 16.427 (1) Å | µ = 8.59 mm−1 |
β = 93.36 (1)° | T = 173 K |
V = 1223.1 (2) Å3 | Parallelepiped, colourless |
Z = 4 | 0.2 × 0.2 × 0.2 mm |
Nonius KappaCCD diffractometer | 2379 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.041 |
Graphite monochromator | θmax = 27.1°, θmin = 2.5° |
Detector resolution: 10 vertical, 18 horizontal pixels mm-1 | h = −13→13 |
626 frames via ω rotation (Δω = 1°) at different θ values and two times 38 s per frame scans | k = −8→8 |
9229 measured reflections | l = −20→20 |
2682 independent reflections |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.024 | H-atom parameters constrained |
wR(F2) = 0.059 | Calculated w = 1/[σ2(Fo2) + (0.0317P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.05 | (Δ/σ)max = 0.001 |
2682 reflections | Δρmax = 0.88 e Å−3 |
113 parameters | Δρmin = −0.93 e Å−3 |
0 restraints | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0025 (3) |
[SnBr2(CH3)2(C5H9NO)] | V = 1223.1 (2) Å3 |
Mr = 407.71 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 10.652 (1) Å | µ = 8.59 mm−1 |
b = 7.002 (1) Å | T = 173 K |
c = 16.427 (1) Å | 0.2 × 0.2 × 0.2 mm |
β = 93.36 (1)° |
Nonius KappaCCD diffractometer | 2379 reflections with I > 2σ(I) |
9229 measured reflections | Rint = 0.041 |
2682 independent reflections |
R[F2 > 2σ(F2)] = 0.024 | 0 restraints |
wR(F2) = 0.059 | H-atom parameters constrained |
S = 1.05 | Δρmax = 0.88 e Å−3 |
2682 reflections | Δρmin = −0.93 e Å−3 |
113 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
Sn1 | 0.811080 (16) | 0.74951 (2) | 0.185142 (10) | 0.02277 (9) | |
Br1 | 0.92241 (3) | 0.61543 (4) | 0.323657 (17) | 0.03551 (10) | |
Br2 | 0.63049 (3) | 0.51577 (3) | 0.184962 (15) | 0.02864 (10) | |
C1 | 0.7468 (3) | 0.9990 (3) | 0.24263 (15) | 0.0299 (6) | |
H1A | 0.8067 | 1.1000 | 0.2375 | 0.045* | |
H1B | 0.7372 | 0.9733 | 0.2993 | 0.045* | |
H1C | 0.6672 | 1.0368 | 0.2171 | 0.045* | |
C2 | 0.9500 (3) | 0.6407 (4) | 0.11158 (17) | 0.0353 (7) | |
H2A | 0.9222 | 0.6532 | 0.0552 | 0.053* | |
H2B | 0.9643 | 0.5083 | 0.1242 | 0.053* | |
H2C | 1.0267 | 0.7109 | 0.1218 | 0.053* | |
O1 | 0.7131 (2) | 0.8522 (3) | 0.06305 (10) | 0.0349 (5) | |
C11 | 0.7122 (3) | 0.9969 (3) | 0.01788 (14) | 0.0246 (6) | |
C12 | 0.7847 (3) | 1.1782 (4) | 0.03235 (16) | 0.0317 (6) | |
H12A | 0.8729 | 1.1600 | 0.0228 | 0.048* | |
H12B | 0.7774 | 1.2239 | 0.0876 | 0.048* | |
C13 | 0.7228 (3) | 1.3176 (4) | −0.02993 (16) | 0.0322 (6) | |
H13A | 0.6603 | 1.3960 | −0.0052 | 0.048* | |
H13B | 0.7849 | 1.4000 | −0.0527 | 0.048* | |
C14 | 0.6613 (3) | 1.1865 (4) | −0.09545 (16) | 0.0314 (6) | |
H14A | 0.5811 | 1.2374 | −0.1164 | 0.047* | |
H14B | 0.7154 | 1.1692 | −0.1403 | 0.047* | |
N1 | 0.6447 (2) | 1.0080 (3) | −0.05207 (12) | 0.0247 (5) | |
C15 | 0.5759 (3) | 0.8472 (4) | −0.08914 (16) | 0.0337 (6) | |
H15A | 0.6190 | 0.8014 | −0.1350 | 0.051* | |
H15B | 0.4927 | 0.8876 | −0.1071 | 0.051* | |
H15C | 0.5705 | 0.7467 | −0.0498 | 0.051* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Sn1 | 0.02696 (14) | 0.01880 (12) | 0.02245 (13) | 0.00207 (6) | 0.00053 (9) | 0.00061 (6) |
Br1 | 0.03496 (19) | 0.03579 (17) | 0.03442 (17) | −0.00065 (12) | −0.00950 (13) | 0.00971 (11) |
Br2 | 0.03064 (18) | 0.02591 (15) | 0.02893 (16) | −0.00345 (10) | −0.00191 (12) | 0.00106 (10) |
C1 | 0.0378 (17) | 0.0252 (12) | 0.0266 (14) | 0.0062 (11) | 0.0017 (12) | −0.0024 (10) |
C2 | 0.0341 (17) | 0.0335 (15) | 0.0394 (16) | 0.0022 (12) | 0.0103 (13) | −0.0070 (12) |
O1 | 0.0518 (13) | 0.0280 (10) | 0.0240 (10) | 0.0012 (9) | −0.0051 (9) | 0.0071 (7) |
C11 | 0.0283 (15) | 0.0276 (13) | 0.0180 (12) | 0.0068 (10) | 0.0012 (11) | −0.0004 (10) |
C12 | 0.0368 (16) | 0.0303 (13) | 0.0276 (14) | −0.0014 (12) | −0.0031 (12) | 0.0003 (11) |
C13 | 0.0438 (18) | 0.0246 (13) | 0.0286 (14) | 0.0010 (12) | 0.0065 (13) | 0.0013 (11) |
C14 | 0.0397 (17) | 0.0271 (13) | 0.0271 (14) | 0.0057 (12) | 0.0006 (13) | 0.0052 (11) |
N1 | 0.0303 (13) | 0.0241 (10) | 0.0194 (10) | 0.0030 (9) | −0.0012 (9) | 0.0021 (8) |
C15 | 0.0373 (17) | 0.0337 (14) | 0.0299 (14) | −0.0029 (12) | 0.0009 (13) | −0.0022 (11) |
Sn1—C2 | 2.107 (3) | C12—C13 | 1.535 (4) |
Sn1—C1 | 2.119 (2) | C12—H12A | 0.9700 |
Sn1—O1 | 2.3205 (17) | C12—H12B | 0.9700 |
Sn1—Br2 | 2.5256 (4) | C13—C14 | 1.532 (4) |
Sn1—Br1 | 2.6737 (4) | C13—H13A | 0.9700 |
C1—H1A | 0.9600 | C13—H13B | 0.9700 |
C1—H1B | 0.9600 | C14—N1 | 1.454 (3) |
C1—H1C | 0.9600 | C14—H14A | 0.9700 |
C2—H2A | 0.9600 | C14—H14B | 0.9700 |
C2—H2B | 0.9600 | N1—C15 | 1.458 (3) |
C2—H2C | 0.9600 | C15—H15A | 0.9600 |
O1—C11 | 1.256 (3) | C15—H15B | 0.9600 |
C11—N1 | 1.321 (3) | C15—H15C | 0.9600 |
C11—C12 | 1.498 (4) | ||
C2—Sn1—C1 | 144.11 (11) | C11—C12—H12A | 111.0 |
C2—Sn1—O1 | 84.94 (10) | C13—C12—H12A | 111.0 |
C1—Sn1—O1 | 89.35 (9) | C11—C12—H12B | 111.0 |
C2—Sn1—Br2 | 108.98 (8) | C13—C12—H12B | 111.0 |
C1—Sn1—Br2 | 105.58 (8) | H12A—C12—H12B | 109.0 |
O1—Sn1—Br2 | 84.02 (5) | C14—C13—C12 | 103.7 (2) |
C2—Sn1—Br1 | 94.00 (8) | C14—C13—H13A | 111.0 |
C1—Sn1—Br1 | 92.82 (7) | C12—C13—H13A | 111.0 |
O1—Sn1—Br1 | 177.50 (5) | C14—C13—H13B | 111.0 |
Br2—Sn1—Br1 | 94.201 (12) | C12—C13—H13B | 111.0 |
Sn1—C1—H1A | 109.5 | H13A—C13—H13B | 109.0 |
Sn1—C1—H1B | 109.5 | N1—C14—C13 | 103.3 (2) |
H1A—C1—H1B | 109.5 | N1—C14—H14A | 111.1 |
Sn1—C1—H1C | 109.5 | C13—C14—H14A | 111.1 |
H1A—C1—H1C | 109.5 | N1—C14—H14B | 111.1 |
H1B—C1—H1C | 109.5 | C13—C14—H14B | 111.1 |
Sn1—C2—H2A | 109.5 | H14A—C14—H14B | 109.1 |
Sn1—C2—H2B | 109.5 | C11—N1—C14 | 113.7 (2) |
H2A—C2—H2B | 109.5 | C11—N1—C15 | 123.5 (2) |
Sn1—C2—H2C | 109.5 | C14—N1—C15 | 122.1 (2) |
H2A—C2—H2C | 109.5 | N1—C15—H15A | 109.5 |
H2B—C2—H2C | 109.5 | N1—C15—H15B | 109.5 |
C11—O1—Sn1 | 138.44 (17) | H15A—C15—H15B | 109.5 |
O1—C11—N1 | 123.1 (2) | N1—C15—H15C | 109.5 |
O1—C11—C12 | 127.2 (2) | H15A—C15—H15C | 109.5 |
N1—C11—C12 | 109.7 (2) | H15B—C15—H15C | 109.5 |
C11—C12—C13 | 103.6 (2) | ||
C2—Sn1—O1—C11 | −90.0 (3) | C11—C12—C13—C14 | −22.8 (3) |
C1—Sn1—O1—C11 | 54.5 (3) | C12—C13—C14—N1 | 23.4 (3) |
Br2—Sn1—O1—C11 | 160.3 (3) | O1—C11—N1—C14 | −178.1 (2) |
Br1—Sn1—O1—C11 | −155.2 (10) | C12—C11—N1—C14 | 1.3 (3) |
Sn1—O1—C11—N1 | 178.07 (18) | O1—C11—N1—C15 | −7.5 (4) |
Sn1—O1—C11—C12 | −1.3 (4) | C12—C11—N1—C15 | 172.0 (2) |
O1—C11—C12—C13 | −166.4 (3) | C13—C14—N1—C11 | −16.2 (3) |
N1—C11—C12—C13 | 14.1 (3) | C13—C14—N1—C15 | 173.0 (2) |
Experimental details
Crystal data | |
Chemical formula | [SnBr2(CH3)2(C5H9NO)] |
Mr | 407.71 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 173 |
a, b, c (Å) | 10.652 (1), 7.002 (1), 16.427 (1) |
β (°) | 93.36 (1) |
V (Å3) | 1223.1 (2) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 8.59 |
Crystal size (mm) | 0.2 × 0.2 × 0.2 |
Data collection | |
Diffractometer | Nonius KappaCCD diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 9229, 2682, 2379 |
Rint | 0.041 |
(sin θ/λ)max (Å−1) | 0.641 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.024, 0.059, 1.05 |
No. of reflections | 2682 |
No. of parameters | 113 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.88, −0.93 |
Computer programs: Nonius KappaCCD software, DENZO and SCALEPACK (Otwinowski & Minor, 1997), SHELXS97 (Sheldrick, 1990), SHELXL97 (Sheldrick, 1997) and PARST95 (Nardelli, 1995).
Recently, molecular complexes derived from 1:2 complexation of dimethyltin dihalides by N-methylpyrrolidinone (NMP) have been presented (König et al., 2000); these have a distorted octahedral geometry. Complexes of dimethyltin dihalides with a single ligand such as DMF, DMSO or HMPT are less well known because several such electron-donor solvents favour a 1:2 composition. The 1:1 reaction of dimethyltin dibromide with NMP leads to the formation of the title complex.
In the crystal of the title compound, the atoms bound to the Sn atom form a distorted trigonal–bipyramidal geometry. The angle between the two axial ligands NMP and Br2 is 177.50 (5)° and thus close to the ideal angle of 180°. The deviation from ideal geometry is manifested most clearly by the widened C1—Sn—C2 angle of 144.11 (11)° and by the narrowed C1—Sn—Br2 and C2—Sn—Br2 angles of 105.58 (8) and 108.98 (8)°, respectively, compared with a value of 120° for an ideal angle in the equatorial plane. This plane contains two methyl groups and one bromine and is displaced somewhat towards the axial NMP ligand. This becomes obvious from the values of the angles between the equatorial and axial ligands: (i) O1—Sn1—C1 89.35 (9)°, O1—Sn1—C2 84.94 (10)° and O1—Sn1—Br2 84.02 (5)°; (ii) Br1—Sn1—C1 92.82 (7)°, Br1—Sn1—C2 94.00 (8)° and Br1—Sn1—Br2 94.201 (12)°. This geometry has been observed for five other coordinated dimethyltin dihalide complexes (Matsubayashi et al., 1968; Liengme et al., 1972). The Sn—C bond lengths of the title compound [2.107 (3) and 2.119 (2) Å] are in the range of previously reported values of dimethyltin dihalide complexes with NMP ligands (König et al., 2000) and of other five-coordinated methyltin species (Clark et al., 1964; Schlemper & Britton, 1966; Forder & Sheldrick, 1970). The Sn—O bond length in this compound [2.3205 (17) Å] also correlates with known values (König et al., 2000). The two Sn—Br bond lengths in the title compound differ, the values being as follows: (i) Sn—Brax 2.6737 (4) Å; (ii) Sn—Breq 2.5256 (4) Å. The Sn—Br bond length in the equatorial plane is comparable with reported values of uncomplexed dimethyltin dibromide (Skinner & Sutton, 1944) and (4-bromo-1,2,3,4-tetraphenyl-cis,cis-1,3-butadienyl)dimethyltin bromide (Boer et al., 1970). The bond length between tin and the axial bromine ligand is in the range found for cis-dibromo-trans-dimethyl-cis-bis(N-methylpyrrolidinone)tin(IV) (König et al., 2000). The values of the bond lengths and bond angles in the NMP ligand are comparable with those observed in other NMP coordinated organometallic compounds (Churchill & Rotella, 1979) and in free NMP (Müller et al., 1996). The torsion angles vary from 1.3° for C12—C11—N1—C14 to 23.4° for C12—C13—C14—N1, these values in uncomplexed NMP being 4.5 and 19.8°, respectively.