organic compounds
2-[(2-Hydroxy-2,2-diphenylethyl)(methyl)amino]-N,N-dimethylethanaminium bromide
aAnorganische Chemie, Technische Universität Dortmund, Otto-Hahn-Strasse 6, 44227 Dortmund, Germany
*Correspondence e-mail: mail@carsten-strohmann.de
The title compound, C19H27N2O+·Br−, is the hydrobromide of the trapping product of lithiated N,N,N′,N′-tetramethylethylenediamine (TMEDA) with benzophenone. Thereby, the N atom of the NMe2 group is selectively protonated and the respective trapping product represents a potential tridentate ligand with one O and two N donor atoms. The H atoms at N (H2N) and O (H1O) are involved in hydrogen bonds with the Br−. The molecular structure shows all donor atoms to be arranged on one side of the molecule, thus indicating a potential threefold coordination of a Lewis acid.
Related literature
For related literature on direct deprotonation of tertiary a,b,c, 2008a,b), Gessner & Strohmann (2008); Bojer et al. (2007); Karsch (1996); Strohmann et al. (2008); Köhler et al. (1987); Arnold et al. (2002).
see: Strohmann & Gessner (2007Experimental
Crystal data
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Refinement
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Data collection: SMART (Bruker, 2001); cell SAINT-Plus (Bruker, 1999); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS90 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97.
Supporting information
10.1107/S1600536809002414/im2095sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809002414/im2095Isup2.hkl
2-(2-Dimethylaminoethyl)(methyl)amino-1,1-diphenylethanol and an equivalent amount of LiBr were dissolved in a mixture of acetone and a few trops acetic acid and stored at room temperature for 24 h. After evaporation of the solvent a crystalline solid remained, suitable for X-ray studies.
1H NMR (400.1 MHz, D2O): δ = 2.17 (s, 3H; N(CH3)CH2), 2.42 (s, 6H; N(CH3)2), 2,68 (t, 3JHH = 6.16 Hz, 3H; CH2N), 2.95 (t, 3JHH = 6.14 Hz, 2H; CH2N), 3.43 (s, 2H; NCH2C(OH)Ph2), 6.60–7.10 (br, 2H; NH and OH), 7.20–7.24 (m, 2H; Hpara), 7.24–2.33 (m, 4H; Harom), 7.41–2.43 (m, 4H; Harom).
{1H}13C NMR (100.6 MHz, D2O): δ = 42.4 (HN(CH3)2), 43.7 (N(CH3)CH2), 52.9 (CH2N(H)(CH3)2), 55.1 (CH2CH2N(CH3)CH2), 66.6 (NCH2C(OH)Ph2), 78.1 (CPh2), 125.9 (Cmeta), 1276.4 (Cpara), 128.6 (Cortho), 145.3 (Cipso).
Refinement was accomplished by full-matrix least-squares methods (based on Fo2, SHELXL97); anisotropic thermal parameters for all non-H atoms in the final cycles; the H atoms were calculated into idealized positions and refined using a riding model with Uiso(H) = 1.2Ueq(C) for CH and CH2 groups and 1.5Ueq(C) for methyl groups. The positions of H2N and H1O were determined from the difference Fourier map and they were refined without constraints.
Data collection: SMART (Bruker, 2001); cell
SAINT-Plus (Bruker, 1999); data reduction: SAINT-Plus (Bruker, 1999); program(s) used to solve structure: SHELXS90 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).Fig. 1. ORTEP plot of 2-[(2'-Hydroxy-2',2'-diphenylethyl)-N'-methyl(amino)]-N,N-dimethylethanaminium bromide. Thermal ellipsoids are drawn at the 50% probability level. |
C19H27N2O+·Br− | F(000) = 1584 |
Mr = 379.34 | Dx = 1.358 Mg m−3 |
Orthorhombic, Pbca | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ac 2ab | θ = 1.2–26° |
a = 7.119 (2) Å | µ = 2.22 mm−1 |
b = 15.515 (3) Å | T = 173 K |
c = 33.585 (7) Å | Needle, colourless |
V = 3710 (1) Å3 | 0.4 × 0.2 × 0.2 mm |
Z = 8 |
Bruker APEX CCD diffractometer | 3640 independent reflections |
Radiation source: fine-focus sealed tube | 3200 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.064 |
ω scans | θmax = 26°, θmin = 1.2° |
Absorption correction: empirical (using intensity measurements) (SADABS; Bruker, 1999) | h = −8→8 |
Tmin = 0.440, Tmax = 0.635 | k = −19→19 |
78737 measured reflections | l = −41→41 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.037 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.099 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.07 | w = 1/[σ2(Fo2) + (0.0504P)2 + 4.0375P] where P = (Fo2 + 2Fc2)/3 |
3640 reflections | (Δ/σ)max = 0.003 |
219 parameters | Δρmax = 0.49 e Å−3 |
0 restraints | Δρmin = −0.43 e Å−3 |
C19H27N2O+·Br− | V = 3710 (1) Å3 |
Mr = 379.34 | Z = 8 |
Orthorhombic, Pbca | Mo Kα radiation |
a = 7.119 (2) Å | µ = 2.22 mm−1 |
b = 15.515 (3) Å | T = 173 K |
c = 33.585 (7) Å | 0.4 × 0.2 × 0.2 mm |
Bruker APEX CCD diffractometer | 3640 independent reflections |
Absorption correction: empirical (using intensity measurements) (SADABS; Bruker, 1999) | 3200 reflections with I > 2σ(I) |
Tmin = 0.440, Tmax = 0.635 | Rint = 0.064 |
78737 measured reflections |
R[F2 > 2σ(F2)] = 0.037 | 0 restraints |
wR(F2) = 0.099 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.07 | Δρmax = 0.49 e Å−3 |
3640 reflections | Δρmin = −0.43 e Å−3 |
219 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 | ||
Br | 0.55743 (4) | 0.697337 (19) | 0.564819 (9) | 0.03232 (11) | |
C1 | 0.5689 (4) | 0.93459 (17) | 0.63574 (8) | 0.0250 (6) | |
C2 | 0.6972 (4) | 0.88169 (17) | 0.66284 (8) | 0.0250 (6) | |
C3 | 0.8583 (4) | 0.9173 (2) | 0.67970 (9) | 0.0320 (7) | |
H3 | 0.8892 | 0.9757 | 0.6743 | 0.038* | |
C4 | 0.9747 (5) | 0.8691 (2) | 0.70430 (9) | 0.0406 (8) | |
H4 | 1.0839 | 0.8946 | 0.7155 | 0.049* | |
C5 | 0.9321 (5) | 0.7848 (2) | 0.71242 (10) | 0.0450 (9) | |
H5 | 1.0122 | 0.7516 | 0.7291 | 0.054* | |
C6 | 0.7726 (5) | 0.7483 (2) | 0.69634 (10) | 0.0429 (8) | |
H6 | 0.7427 | 0.6900 | 0.7021 | 0.052* | |
C7 | 0.6550 (5) | 0.79621 (19) | 0.67180 (9) | 0.0332 (7) | |
H7 | 0.5451 | 0.7704 | 0.6611 | 0.040* | |
C8 | 0.4435 (4) | 0.99595 (17) | 0.65971 (8) | 0.0263 (6) | |
C9 | 0.4565 (4) | 1.0055 (2) | 0.70069 (9) | 0.0335 (7) | |
H9 | 0.5476 | 0.9736 | 0.7151 | 0.040* | |
C10 | 0.3373 (5) | 1.0615 (2) | 0.72079 (9) | 0.0380 (7) | |
H10 | 0.3473 | 1.0671 | 0.7489 | 0.046* | |
C11 | 0.2045 (5) | 1.1091 (2) | 0.70046 (10) | 0.0372 (7) | |
H11 | 0.1250 | 1.1480 | 0.7143 | 0.045* | |
C12 | 0.1884 (4) | 1.09930 (19) | 0.65969 (9) | 0.0337 (7) | |
H12 | 0.0965 | 1.1312 | 0.6454 | 0.040* | |
C13 | 0.3059 (4) | 1.04315 (18) | 0.63960 (9) | 0.0290 (6) | |
H13 | 0.2928 | 1.0366 | 0.6116 | 0.035* | |
C14 | 0.6829 (4) | 0.98676 (17) | 0.60473 (8) | 0.0285 (6) | |
H14A | 0.5987 | 1.0285 | 0.5914 | 0.034* | |
H14B | 0.7824 | 1.0198 | 0.6186 | 0.034* | |
C15 | 0.6945 (5) | 0.9484 (2) | 0.53493 (9) | 0.0402 (8) | |
H15A | 0.7315 | 1.0066 | 0.5267 | 0.060* | |
H15B | 0.5572 | 0.9443 | 0.5355 | 0.060* | |
H15C | 0.7445 | 0.9062 | 0.5160 | 0.060* | |
C16 | 0.9753 (4) | 0.93415 (19) | 0.57482 (9) | 0.0289 (6) | |
H16A | 1.0205 | 0.9333 | 0.6027 | 0.035* | |
H16B | 1.0168 | 0.9890 | 0.5626 | 0.035* | |
C17 | 1.0617 (4) | 0.85949 (18) | 0.55238 (9) | 0.0288 (6) | |
H17A | 1.0360 | 0.8664 | 0.5236 | 0.035* | |
H17B | 1.1995 | 0.8603 | 0.5562 | 0.035* | |
C18 | 1.0397 (5) | 0.70427 (19) | 0.53833 (10) | 0.0345 (7) | |
H18A | 1.1761 | 0.6960 | 0.5392 | 0.052* | |
H18B | 1.0018 | 0.7198 | 0.5112 | 0.052* | |
H18C | 0.9767 | 0.6508 | 0.5462 | 0.052* | |
C19 | 1.0432 (4) | 0.7534 (2) | 0.60756 (9) | 0.0344 (7) | |
H19A | 0.9805 | 0.7002 | 0.6161 | 0.052* | |
H19B | 1.0071 | 0.8007 | 0.6253 | 0.052* | |
H19C | 1.1796 | 0.7453 | 0.6086 | 0.052* | |
N1 | 0.7695 (3) | 0.93059 (15) | 0.57460 (7) | 0.0262 (5) | |
N2 | 0.9858 (4) | 0.77440 (16) | 0.56609 (7) | 0.0260 (5) | |
H2N | 0.864 (6) | 0.779 (2) | 0.5669 (10) | 0.044 (10)* | |
O | 0.4411 (3) | 0.88041 (14) | 0.61458 (7) | 0.0298 (5) | |
H1O | 0.494 (5) | 0.849 (2) | 0.6050 (10) | 0.024 (10)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Br | 0.02792 (17) | 0.03281 (18) | 0.03624 (18) | −0.00315 (12) | 0.00142 (12) | −0.00227 (12) |
C1 | 0.0251 (14) | 0.0217 (13) | 0.0283 (14) | −0.0032 (11) | −0.0027 (12) | −0.0014 (11) |
C2 | 0.0242 (14) | 0.0256 (14) | 0.0252 (13) | 0.0005 (11) | 0.0033 (11) | 0.0001 (11) |
C3 | 0.0301 (16) | 0.0327 (15) | 0.0333 (16) | −0.0008 (13) | −0.0003 (13) | −0.0044 (12) |
C4 | 0.0297 (17) | 0.062 (2) | 0.0301 (16) | 0.0028 (16) | −0.0057 (13) | −0.0061 (15) |
C5 | 0.047 (2) | 0.058 (2) | 0.0308 (17) | 0.0190 (17) | −0.0028 (15) | 0.0079 (15) |
C6 | 0.048 (2) | 0.0371 (17) | 0.0432 (18) | 0.0083 (16) | 0.0076 (16) | 0.0158 (15) |
C7 | 0.0315 (16) | 0.0310 (15) | 0.0371 (16) | −0.0041 (13) | 0.0020 (14) | 0.0034 (13) |
C8 | 0.0249 (14) | 0.0217 (13) | 0.0324 (15) | −0.0050 (11) | −0.0008 (12) | −0.0002 (11) |
C9 | 0.0331 (17) | 0.0347 (16) | 0.0327 (16) | −0.0002 (14) | −0.0033 (13) | −0.0013 (13) |
C10 | 0.0387 (18) | 0.0446 (18) | 0.0309 (16) | −0.0019 (15) | 0.0036 (14) | −0.0070 (14) |
C11 | 0.0328 (17) | 0.0306 (15) | 0.0481 (19) | −0.0004 (14) | 0.0075 (14) | −0.0079 (14) |
C12 | 0.0261 (15) | 0.0286 (15) | 0.0464 (18) | −0.0006 (13) | 0.0023 (13) | 0.0022 (13) |
C13 | 0.0281 (15) | 0.0266 (14) | 0.0322 (15) | −0.0029 (12) | −0.0012 (12) | 0.0007 (12) |
C14 | 0.0335 (16) | 0.0203 (13) | 0.0316 (15) | 0.0005 (12) | −0.0005 (13) | 0.0006 (11) |
C15 | 0.0403 (18) | 0.0470 (19) | 0.0334 (16) | 0.0054 (16) | −0.0093 (14) | −0.0049 (14) |
C16 | 0.0276 (15) | 0.0301 (15) | 0.0289 (14) | −0.0067 (12) | −0.0014 (12) | −0.0005 (12) |
C17 | 0.0252 (15) | 0.0317 (15) | 0.0295 (14) | −0.0032 (12) | 0.0022 (12) | 0.0041 (12) |
C18 | 0.0328 (17) | 0.0323 (16) | 0.0384 (17) | 0.0026 (13) | 0.0037 (14) | −0.0078 (13) |
C19 | 0.0347 (17) | 0.0362 (16) | 0.0325 (15) | 0.0051 (14) | −0.0004 (13) | 0.0063 (13) |
N1 | 0.0266 (12) | 0.0263 (12) | 0.0255 (11) | −0.0010 (10) | −0.0018 (10) | −0.0005 (9) |
N2 | 0.0198 (12) | 0.0276 (12) | 0.0306 (13) | 0.0001 (10) | 0.0033 (10) | 0.0010 (10) |
O | 0.0274 (11) | 0.0255 (11) | 0.0365 (12) | −0.0004 (9) | −0.0045 (9) | −0.0082 (9) |
C1—O | 1.428 (3) | C13—H13 | 0.9500 |
C1—C2 | 1.528 (4) | C14—N1 | 1.471 (4) |
C1—C8 | 1.534 (4) | C14—H14A | 0.9900 |
C1—C14 | 1.549 (4) | C14—H14B | 0.9900 |
C2—C7 | 1.393 (4) | C15—N1 | 1.462 (4) |
C2—C3 | 1.393 (4) | C15—H15A | 0.9800 |
C3—C4 | 1.388 (4) | C15—H15B | 0.9800 |
C3—H3 | 0.9500 | C15—H15C | 0.9800 |
C4—C5 | 1.370 (5) | C16—N1 | 1.466 (4) |
C4—H4 | 0.9500 | C16—C17 | 1.513 (4) |
C5—C6 | 1.379 (5) | C16—H16A | 0.9900 |
C5—H5 | 0.9500 | C16—H16B | 0.9900 |
C6—C7 | 1.390 (5) | C17—N2 | 1.499 (4) |
C6—H6 | 0.9500 | C17—H17A | 0.9900 |
C7—H7 | 0.9500 | C17—H17B | 0.9900 |
C8—C9 | 1.387 (4) | C18—N2 | 1.483 (4) |
C8—C13 | 1.397 (4) | C18—H18A | 0.9800 |
C9—C10 | 1.389 (4) | C18—H18B | 0.9800 |
C9—H9 | 0.9500 | C18—H18C | 0.9800 |
C10—C11 | 1.380 (5) | C19—N2 | 1.487 (4) |
C10—H10 | 0.9500 | C19—H19A | 0.9800 |
C11—C12 | 1.382 (4) | C19—H19B | 0.9800 |
C11—H11 | 0.9500 | C19—H19C | 0.9800 |
C12—C13 | 1.383 (4) | N2—H2N | 0.87 (4) |
C12—H12 | 0.9500 | O—H1O | 0.69 (3) |
O—C1—C2 | 111.2 (2) | C1—C14—H14A | 109.2 |
O—C1—C8 | 104.8 (2) | N1—C14—H14B | 109.2 |
C2—C1—C8 | 111.6 (2) | C1—C14—H14B | 109.2 |
O—C1—C14 | 107.9 (2) | H14A—C14—H14B | 107.9 |
C2—C1—C14 | 111.6 (2) | N1—C15—H15A | 109.5 |
C8—C1—C14 | 109.5 (2) | N1—C15—H15B | 109.5 |
C7—C2—C3 | 117.8 (3) | H15A—C15—H15B | 109.5 |
C7—C2—C1 | 120.7 (3) | N1—C15—H15C | 109.5 |
C3—C2—C1 | 121.4 (2) | H15A—C15—H15C | 109.5 |
C4—C3—C2 | 121.3 (3) | H15B—C15—H15C | 109.5 |
C4—C3—H3 | 119.3 | N1—C16—C17 | 112.0 (2) |
C2—C3—H3 | 119.3 | N1—C16—H16A | 109.2 |
C5—C4—C3 | 120.0 (3) | C17—C16—H16A | 109.2 |
C5—C4—H4 | 120.0 | N1—C16—H16B | 109.2 |
C3—C4—H4 | 120.0 | C17—C16—H16B | 109.2 |
C4—C5—C6 | 119.7 (3) | H16A—C16—H16B | 107.9 |
C4—C5—H5 | 120.2 | N2—C17—C16 | 112.0 (2) |
C6—C5—H5 | 120.2 | N2—C17—H17A | 109.2 |
C5—C6—C7 | 120.6 (3) | C16—C17—H17A | 109.2 |
C5—C6—H6 | 119.7 | N2—C17—H17B | 109.2 |
C7—C6—H6 | 119.7 | C16—C17—H17B | 109.2 |
C2—C7—C6 | 120.5 (3) | H17A—C17—H17B | 107.9 |
C2—C7—H7 | 119.8 | N2—C18—H18A | 109.5 |
C6—C7—H7 | 119.8 | N2—C18—H18B | 109.5 |
C9—C8—C13 | 118.0 (3) | H18A—C18—H18B | 109.5 |
C9—C8—C1 | 123.3 (3) | N2—C18—H18C | 109.5 |
C13—C8—C1 | 118.7 (2) | H18A—C18—H18C | 109.5 |
C8—C9—C10 | 120.6 (3) | H18B—C18—H18C | 109.5 |
C8—C9—H9 | 119.7 | N2—C19—H19A | 109.5 |
C10—C9—H9 | 119.7 | N2—C19—H19B | 109.5 |
C11—C10—C9 | 120.8 (3) | H19A—C19—H19B | 109.5 |
C11—C10—H10 | 119.6 | N2—C19—H19C | 109.5 |
C9—C10—H10 | 119.6 | H19A—C19—H19C | 109.5 |
C12—C11—C10 | 119.2 (3) | H19B—C19—H19C | 109.5 |
C12—C11—H11 | 120.4 | C15—N1—C16 | 111.3 (2) |
C10—C11—H11 | 120.4 | C15—N1—C14 | 111.2 (2) |
C11—C12—C13 | 120.1 (3) | C16—N1—C14 | 113.2 (2) |
C11—C12—H12 | 119.9 | C18—N2—C19 | 110.9 (2) |
C13—C12—H12 | 119.9 | C18—N2—C17 | 111.1 (2) |
C12—C13—C8 | 121.2 (3) | C19—N2—C17 | 112.5 (2) |
C12—C13—H13 | 119.4 | C18—N2—H2N | 110 (2) |
C8—C13—H13 | 119.4 | C19—N2—H2N | 105 (2) |
N1—C14—C1 | 111.9 (2) | C17—N2—H2N | 107 (2) |
N1—C14—H14A | 109.2 | C1—O—H1O | 107 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2N···Br | 0.87 (4) | 2.52 (4) | 3.276 (3) | 145 (4) |
O—H1O···Br | 0.69 (3) | 2.76 (3) | 3.398 (2) | 156 (3) |
Experimental details
Crystal data | |
Chemical formula | C19H27N2O+·Br− |
Mr | 379.34 |
Crystal system, space group | Orthorhombic, Pbca |
Temperature (K) | 173 |
a, b, c (Å) | 7.119 (2), 15.515 (3), 33.585 (7) |
V (Å3) | 3710 (1) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 2.22 |
Crystal size (mm) | 0.4 × 0.2 × 0.2 |
Data collection | |
Diffractometer | Bruker APEX CCD diffractometer |
Absorption correction | Empirical (using intensity measurements) (SADABS; Bruker, 1999) |
Tmin, Tmax | 0.440, 0.635 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 78737, 3640, 3200 |
Rint | 0.064 |
(sin θ/λ)max (Å−1) | 0.617 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.037, 0.099, 1.07 |
No. of reflections | 3640 |
No. of parameters | 219 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.49, −0.43 |
Computer programs: SMART (Bruker, 2001), SAINT-Plus (Bruker, 1999), SHELXS90 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997).
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2N···Br | 0.87 (4) | 2.52 (4) | 3.276 (3) | 145 (4) |
O—H1O···Br | 0.69 (3) | 2.76 (3) | 3.398 (2) | 156 (3) |
Acknowledgements
The authors are grateful to the Deutsche Forschungsgemeinschaft and the Fonds der Chemischen Industrie for financial support and the award of a scholarship (VHG). CD thanks the Studienstiftung des Deutschen Volkes for a doctoral scholarship.
References
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Due to their application in many fields of chemistry, the preparation of nitrogen ligands is still of great interest in synthetic chemistry. Recent investigations have proved the direct deprotonation of methylamines to be a synthetically very useful method for functionalizations and thus for the synthesis of nitrogen ligands. Further donor atoms as well as further stereocenters can easily be introduced to the molecule. Only few tertiary methylamines are known for their reactivity towards such a direct lithiation reaction, amongst (R,R)-TMCDA (Strohmann & Gessner, 2007a,c, 2008a; Strohmann et al., 2008), PMDTA (Strohmann & Gessner, 2007b) and TMEDA (Gessner & Strohmann, 2008; Köhler et al., 1987). Generally, this type of reaction is an undesired side reaction resulting in the loss of base and leading to side products, e.g. in deprotonation or addition reactions with lithiumalkyls (Arnold et al., 2002). However, this decomposition of the Lewis base can also be used synthetically for the preparation of new ligand systems (Karsch, 1996; Bojer et al., 2007; Strohmann & Gessner, 2008b).
The title compound 2-[(2'-Hydroxy-2',2'-diphenylethyl)-N'-methyl(amino)]-N,N-dimethylethanaminium bromide can be synthesized by direct deprotonation of TMEDA with tert-butyllithium and the subsequent trapping reaction with benzophenone. The yield of this lithiation reaction is limited due to the competitive deprotonation of the ethylene bridge of the ligand. Treatment of the resulting amino alcohol with lithiumbromide under acidic conditions gives the hydrobromide as colorless crystals. The structure indicates a potential threefold coordination as all donor atoms (two N atoms and one oxygen) are arranged at the same side of the molecule.
2-[(2'-Hydroxy-2',2'-diphenylethyl)-N'-methyl(amino)]-N,N-dimethylethanaminium bromide crystallizes in the othorhombic crystal system, space group Pbca. The asymmetric unit contains only one molecule of the monomeric compound.