The structure of the cation in the ylide hydrochloride [Me3NNHC(O)C6H4-Cl-p]Cl·H2O, or C10H14ClN2O+·Cl−·H2O, is compared with that of the free ylide. Protonation lengthens the N—C(O) bond but shortens the C=O and N—N bonds by ∼0.03 Å and increases the dihedral angle between the phenyl and ylide planes.
Supporting information
CCDC reference: 233131
An aqueous solution of the parent ylide was prepared by the method of Morris et al. (2003). It was then added to an equimolar quantity of 0.1 M HCl. The resulting solution was concentrated by heating in a rotarary evaporator to the point where crystals of the title compound precipitated on cooling.
Non-H atoms were refined anisotropically and all H-atoms were initially located from difference syntheses. H atoms bonded to atoms N1 and O1W were refined freely. The positions of other H atoms were finally determined using the HFIX function and riding constraints of SHELXL97 (Sheldrick, 1997), assuming C—H bond lengths of 0.95 and 0.98 Å, respectively, for sp2 and sp3 C atoms. For each methyl group, a single orientation parameter was also refined.
Data collection: Collect (Nonius BV, 2000); cell refinement: HKL SCALEPACK (Otwinowski & Minor 1997); data reduction: HKL DENZO (Otwinowski & Minor 1997) and SCALEPACK; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).
Crystal data top
C10H14ClN2O+·Cl−·H2O | F(000) = 560 |
Mr = 267.15 | Dx = 1.437 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 2648 reflections |
a = 7.0302 (2) Å | θ = 1.0–27.5° |
b = 9.9377 (2) Å | µ = 0.51 mm−1 |
c = 17.8571 (5) Å | T = 100 K |
β = 98.279 (1)° | Needle, colourless |
V = 1234.57 (6) Å3 | 0.4 × 0.12 × 0.12 mm |
Z = 4 | |
Data collection top
Nonius KappaCCD diffractometer | Rint = 0.049 |
CCD rotation images, thick slice scans | θmax = 27.5°, θmin = 2.4° |
10868 measured reflections | h = −9→9 |
2806 independent reflections | k = −12→12 |
2465 reflections with I > 2σ(I) | l = −23→23 |
Refinement top
Refinement on F2 | 0 restraints |
Least-squares matrix: full | H atoms treated by a mixture of independent and constrained refinement |
R[F2 > 2σ(F2)] = 0.030 | w = 1/[σ2(Fo2) + (0.026P)2 + 0.67P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.073 | (Δ/σ)max < 0.001 |
S = 1.05 | Δρmax = 0.35 e Å−3 |
2806 reflections | Δρmin = −0.29 e Å−3 |
160 parameters | |
Crystal data top
C10H14ClN2O+·Cl−·H2O | V = 1234.57 (6) Å3 |
Mr = 267.15 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 7.0302 (2) Å | µ = 0.51 mm−1 |
b = 9.9377 (2) Å | T = 100 K |
c = 17.8571 (5) Å | 0.4 × 0.12 × 0.12 mm |
β = 98.279 (1)° | |
Data collection top
Nonius KappaCCD diffractometer | 2465 reflections with I > 2σ(I) |
10868 measured reflections | Rint = 0.049 |
2806 independent reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.030 | 0 restraints |
wR(F2) = 0.073 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | Δρmax = 0.35 e Å−3 |
2806 reflections | Δρmin = −0.29 e Å−3 |
160 parameters | |
Special details top
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. |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
C1 | 0.6093 (2) | 1.04442 (15) | 0.12359 (8) | 0.0160 (3) | |
H1A | 0.5901 | 1.0478 | 0.0682 | 0.024* | |
H1B | 0.6131 | 1.1362 | 0.1438 | 0.024* | |
H1C | 0.5030 | 0.9949 | 0.1408 | 0.024* | |
C2 | 0.9659 (2) | 1.04958 (15) | 0.12910 (9) | 0.0169 (3) | |
H2A | 1.084 | 0.9986 | 0.1454 | 0.025* | |
H2B | 0.9751 | 1.1382 | 0.1535 | 0.025* | |
H2C | 0.9489 | 1.0609 | 0.074 | 0.025* | |
C3 | 0.8211 (2) | 0.96659 (15) | 0.23638 (8) | 0.0160 (3) | |
H3A | 0.7127 | 0.9174 | 0.2521 | 0.024* | |
H3B | 0.8254 | 1.0578 | 0.2574 | 0.024* | |
H3C | 0.9411 | 0.9196 | 0.2549 | 0.024* | |
C4 | 0.77291 (18) | 0.81360 (14) | 0.04700 (8) | 0.0122 (3) | |
C5 | 0.76383 (18) | 0.66760 (14) | 0.02648 (8) | 0.0123 (3) | |
C6 | 0.83602 (19) | 0.56595 (14) | 0.07634 (8) | 0.0133 (3) | |
H6 | 0.8938 | 0.5883 | 0.1262 | 0.016* | |
C7 | 0.82417 (19) | 0.43234 (14) | 0.05375 (8) | 0.0140 (3) | |
H7 | 0.8735 | 0.3629 | 0.0876 | 0.017* | |
C8 | 0.73898 (19) | 0.40194 (14) | −0.01925 (8) | 0.0138 (3) | |
C9 | 0.66555 (19) | 0.50115 (15) | −0.06997 (8) | 0.0148 (3) | |
H9 | 0.6067 | 0.4782 | −0.1196 | 0.018* | |
C10 | 0.67965 (19) | 0.63441 (14) | −0.04700 (8) | 0.0138 (3) | |
H10 | 0.6319 | 0.7036 | −0.0813 | 0.017* | |
Cl1 | 0.32457 (5) | 0.84579 (3) | 0.262707 (19) | 0.01625 (10) | |
Cl2 | 0.72520 (5) | 0.23452 (3) | −0.04804 (2) | 0.01815 (10) | |
N1 | 0.79562 (17) | 0.83738 (12) | 0.12357 (7) | 0.0126 (2) | |
N2 | 0.79629 (16) | 0.97424 (11) | 0.15125 (6) | 0.0124 (2) | |
O1 | 0.76408 (14) | 0.90229 (10) | −0.00071 (6) | 0.0155 (2) | |
O1W | 0.67018 (16) | 0.66488 (12) | 0.22895 (6) | 0.0202 (2) | |
H1 | 0.758 (3) | 0.7808 (19) | 0.1548 (10) | 0.023 (5)* | |
H1W | 0.558 (3) | 0.696 (2) | 0.2388 (13) | 0.047 (6)* | |
H2W | 0.664 (3) | 0.587 (3) | 0.2300 (14) | 0.056 (8)* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
C1 | 0.0146 (6) | 0.0132 (7) | 0.0195 (7) | 0.0039 (5) | −0.0006 (5) | −0.0017 (6) |
C2 | 0.0155 (7) | 0.0140 (7) | 0.0210 (7) | −0.0044 (5) | 0.0019 (5) | 0.0007 (6) |
C3 | 0.0199 (7) | 0.0149 (7) | 0.0128 (7) | 0.0000 (6) | 0.0006 (5) | −0.0020 (6) |
C4 | 0.0090 (6) | 0.0126 (7) | 0.0151 (6) | 0.0011 (5) | 0.0021 (5) | −0.0001 (6) |
C5 | 0.0097 (6) | 0.0130 (7) | 0.0147 (7) | 0.0008 (5) | 0.0034 (5) | −0.0012 (6) |
C6 | 0.0132 (6) | 0.0138 (7) | 0.0127 (6) | 0.0013 (5) | 0.0017 (5) | −0.0008 (6) |
C7 | 0.0141 (6) | 0.0128 (7) | 0.0155 (7) | 0.0013 (5) | 0.0030 (5) | 0.0017 (6) |
C8 | 0.0128 (6) | 0.0108 (7) | 0.0186 (7) | −0.0013 (5) | 0.0049 (5) | −0.0040 (6) |
C9 | 0.0124 (6) | 0.0179 (7) | 0.0141 (7) | 0.0001 (5) | 0.0014 (5) | −0.0027 (6) |
C10 | 0.0125 (6) | 0.0147 (7) | 0.0141 (7) | 0.0026 (5) | 0.0016 (5) | 0.0013 (6) |
Cl1 | 0.01776 (17) | 0.01201 (17) | 0.01916 (18) | 0.00229 (12) | 0.00327 (12) | 0.00137 (13) |
Cl2 | 0.01974 (18) | 0.01195 (17) | 0.02273 (19) | −0.00116 (13) | 0.00290 (13) | −0.00496 (14) |
N1 | 0.0159 (6) | 0.0073 (6) | 0.0146 (6) | −0.0004 (4) | 0.0027 (4) | −0.0001 (5) |
N2 | 0.0135 (5) | 0.0088 (5) | 0.0145 (6) | 0.0001 (4) | 0.0010 (4) | −0.0011 (5) |
O1 | 0.0176 (5) | 0.0128 (5) | 0.0161 (5) | 0.0006 (4) | 0.0021 (4) | 0.0026 (4) |
O1W | 0.0240 (6) | 0.0121 (6) | 0.0263 (6) | 0.0013 (4) | 0.0099 (4) | 0.0031 (5) |
Geometric parameters (Å, º) top
C1—N2 | 1.5072 (17) | C5—C6 | 1.3931 (19) |
C1—H1A | 0.98 | C5—C10 | 1.3989 (19) |
C1—H1B | 0.98 | C6—C7 | 1.387 (2) |
C1—H1C | 0.98 | C6—H6 | 0.95 |
C2—N2 | 1.5084 (17) | C7—C8 | 1.3872 (19) |
C2—H2A | 0.98 | C7—H7 | 0.95 |
C2—H2B | 0.98 | C8—C9 | 1.387 (2) |
C2—H2C | 0.98 | C8—Cl2 | 1.7399 (14) |
C3—N2 | 1.5069 (17) | C9—C10 | 1.386 (2) |
C3—H3A | 0.98 | C9—H9 | 0.95 |
C3—H3B | 0.98 | C10—H10 | 0.95 |
C3—H3C | 0.98 | N1—N2 | 1.4469 (16) |
C4—O1 | 1.2212 (17) | N1—H1 | 0.860 (19) |
C4—N1 | 1.3739 (18) | O1W—H1W | 0.89 (2) |
C4—C5 | 1.4956 (19) | O1W—H2W | 0.78 (3) |
| | | |
N2—C1—H1A | 109.5 | C7—C6—H6 | 119.8 |
N2—C1—H1B | 109.5 | C5—C6—H6 | 119.8 |
H1A—C1—H1B | 109.5 | C6—C7—C8 | 118.79 (13) |
N2—C1—H1C | 109.5 | C6—C7—H7 | 120.6 |
H1A—C1—H1C | 109.5 | C8—C7—H7 | 120.6 |
H1B—C1—H1C | 109.5 | C9—C8—C7 | 121.90 (13) |
N2—C2—H2A | 109.5 | C9—C8—Cl2 | 119.15 (11) |
N2—C2—H2B | 109.5 | C7—C8—Cl2 | 118.94 (11) |
H2A—C2—H2B | 109.5 | C10—C9—C8 | 118.81 (13) |
N2—C2—H2C | 109.5 | C10—C9—H9 | 120.6 |
H2A—C2—H2C | 109.5 | C8—C9—H9 | 120.6 |
H2B—C2—H2C | 109.5 | C9—C10—C5 | 120.37 (13) |
N2—C3—H3A | 109.5 | C9—C10—H10 | 119.8 |
N2—C3—H3B | 109.5 | C5—C10—H10 | 119.8 |
H3A—C3—H3B | 109.5 | C4—N1—N2 | 119.73 (11) |
N2—C3—H3C | 109.5 | C4—N1—H1 | 122.0 (12) |
H3A—C3—H3C | 109.5 | N2—N1—H1 | 112.3 (12) |
H3B—C3—H3C | 109.5 | N1—N2—C3 | 106.94 (10) |
O1—C4—N1 | 123.85 (13) | N1—N2—C1 | 111.30 (10) |
O1—C4—C5 | 122.22 (12) | C3—N2—C1 | 108.82 (11) |
N1—C4—C5 | 113.92 (12) | N1—N2—C2 | 109.92 (10) |
C6—C5—C10 | 119.64 (13) | C3—N2—C2 | 107.98 (10) |
C6—C5—C4 | 123.24 (12) | C1—N2—C2 | 111.69 (11) |
C10—C5—C4 | 117.13 (12) | H1W—O1W—H2W | 107 (2) |
C7—C6—C5 | 120.48 (13) | | |
| | | |
O1—C4—C5—C6 | 157.62 (13) | Cl2—C8—C9—C10 | −179.04 (10) |
N1—C4—C5—C6 | −21.17 (18) | C8—C9—C10—C5 | −1.0 (2) |
O1—C4—C5—C10 | −21.75 (19) | C6—C5—C10—C9 | 0.9 (2) |
N1—C4—C5—C10 | 159.46 (12) | C4—C5—C10—C9 | −179.76 (12) |
C10—C5—C6—C7 | −0.3 (2) | O1—C4—N1—N2 | 4.53 (19) |
C4—C5—C6—C7 | −179.64 (12) | C5—C4—N1—N2 | −176.70 (11) |
C5—C6—C7—C8 | −0.1 (2) | C4—N1—N2—C3 | 179.31 (11) |
C6—C7—C8—C9 | −0.1 (2) | C4—N1—N2—C1 | 60.57 (15) |
C6—C7—C8—Cl2 | 179.59 (10) | C4—N1—N2—C2 | −63.71 (14) |
C7—C8—C9—C10 | 0.6 (2) | | |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O1W | 0.86 (2) | 1.92 (2) | 2.7813 (17) | 176 (2) |
O1W—H1W···Cl1 | 0.89 (2) | 2.30 (2) | 3.1497 (12) | 160 (2) |
O1W—H2W···Cl1i | 0.78 (3) | 2.40 (3) | 3.1745 (12) | 175 (2) |
Symmetry code: (i) −x+1, y−1/2, −z+1/2. |
Experimental details
Crystal data |
Chemical formula | C10H14ClN2O+·Cl−·H2O |
Mr | 267.15 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 100 |
a, b, c (Å) | 7.0302 (2), 9.9377 (2), 17.8571 (5) |
β (°) | 98.279 (1) |
V (Å3) | 1234.57 (6) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.51 |
Crystal size (mm) | 0.4 × 0.12 × 0.12 |
|
Data collection |
Diffractometer | Nonius KappaCCD diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10868, 2806, 2465 |
Rint | 0.049 |
(sin θ/λ)max (Å−1) | 0.649 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.030, 0.073, 1.05 |
No. of reflections | 2806 |
No. of parameters | 160 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.35, −0.29 |
Selected geometric parameters (Å, º) topC4—O1 | 1.2212 (17) | C4—C5 | 1.4956 (19) |
C4—N1 | 1.3739 (18) | N1—N2 | 1.4469 (16) |
| | | |
O1—C4—N1 | 123.85 (13) | C4—N1—N2 | 119.73 (11) |
O1—C4—C5 | 122.22 (12) | C4—N1—H1 | 122.0 (12) |
N1—C4—C5 | 113.92 (12) | N2—N1—H1 | 112.3 (12) |
| | | |
N1—C4—C5—C6 | −21.17 (18) | C5—C4—N1—N2 | −176.70 (11) |
N1—C4—C5—C10 | 159.46 (12) | C4—N1—N2—C3 | 179.31 (11) |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O1W | 0.86 (2) | 1.92 (2) | 2.7813 (17) | 176 (2) |
O1W—H1W···Cl1 | 0.89 (2) | 2.30 (2) | 3.1497 (12) | 160 (2) |
O1W—H2W···Cl1i | 0.78 (3) | 2.40 (3) | 3.1745 (12) | 175 (2) |
Symmetry code: (i) −x+1, y−1/2, −z+1/2. |
The structures of trimethylammonio-nitrogen ylides, Me3N(+)—N(-)—X, (I), are known for many of the common electron-withdrawing stabilizing groups X, such as C(O)C6H4—Cl-p [(Ia); Morris et al., 2003], P(O)Ph2 [(Ib); Muir et al., 1999], SO2Tol [(Ic); Cameron et al., 1976], C6Cl3N2 [(Id); Kartsev et al., 1994], C(O)Ph [(Ie); Cameron et al., 1972] and NO2 [(If); Smith et al., 1997; Cameron et al., 1972]. These compounds are bases and form hydrochlorides [Me3N—NH—X]+Cl−, (II). In the course of studying the ability of nitrogen ylides, (I), to act as ligands (Morris et al., 2003), we were surprised to find that there is no structural example of a corresponding hydrochloride, (II) (QUEST and CONQUEST search programs were used with Version 5.24 of the Cambridge Structural Database (Allen, 2002; 272066 entries, November 2002) to obtain results not otherwise accessible]. Accordingly, we report here the structure of (IIa), X = C(O)C6H4—Cl-p, and compare it with that of its parent ylide, (Ia).
Crystals of (IIa) contain equal numbers of [Me3NNHC(O)C6H4—Cl-p]+ cations, Cl− anions and water molecules. Conventional hydrogen bonds link the Cl− anions and water molecules into infinite chains (Fig. 1 and Table 2) running along b: each H2O unit bridges Cl− ions related by the operation of a 21 screw axis. An N—H···O hydrogen bond links each cation to a chain. The structure also contains C—H···Cl hydrogen bonds [C1···Cl1ii = 3.611 (2) Å and C3···Cl1iii = 3.703 (2) Å; symmetry codes: (ii) 1 − x, 1/2 + y, 1/2 − z; (iii) 1 + x, y, z] and π–π interactions between interleaved phenyl rings (see Fig. 2), which lead to several short C···C contacts, the shortest being C6···C8iv [3.308 (2) Å; symmetry code: (iv) 2 − x, 1 − y, −z] and C8···C10v [3.346 (2) Å;symmetry code: (v) 1 − x, 1 − y, −z]. Except for the C1—H···Cl1ii hydrogen bond, these interactions link different chains together.
Protonation of (Ia) at atom N1 causes only minor changes in conformation and bonding. The N1—C4—C5–C6 torsion angle opens from −5.1 (2)° in (Ia) to −21.2 (2)° in (IIa), thereby relieving the intramolecular H1···H6 contact of 2.23 Å. In (IIa), atoms Cl2 and C4–C10 are coplanar to within 0.008 (1) Å, and the sequence C3—N2—N1—C4—C5 is nearly planar, with torsion angles across N2—N1 and N1—C4 of 179.3 (1) and −176.7 (1)° [cf. 178.7 (1) and −179.7 (1)° in (Ia)]. The N1—C4 and C4—O1 bond lengths in (IIa) [1.374 (2) and 1.221 (2) Å] are respectively longer and shorter than corresponding values in (Ia) [1.338 (2) and 1.258 (2) Å] and (Ie) [1.313 (6) and 1.243 (5) Å], indicating less delocalization across the N—C bond in the hydrochloride, though rehydridization at atom N1 may also be significant (see below). More surprisingly, given the larger coordination number of atom N1 in (IIa), its N1—N2 bond [1.447 (2) Å] is shorter than the value in (Ia) [1.474 (2) Å]. N—N bonds in (Ia)–(If) fall in the narrow range 1.470–1.476 Å, except for the value in (Ib) [1.450 (4) Å]. The N2—N1—C4 angle in (IIa) of 119.7 (1)° is more obtuse than the values in (Ia) [113.5 (1)°] or (Ie) [114.2 (3)°]. A change in the hybridization at atom N1, so that it contributes more s-character to the N1—N2 and N1—C4 bonds of (IIa) than to the corresponding bonds of (Ia), would explain these trends. Although the zwitterion Me3N(+)NHCH2CH2CO2− is formally analogous to (II), its three-coordinate N atom is linked to the unsaturated –CO2− group through a fully saturated C atom, resulting in marked differences in coordination [N—N = 1.491, N—C = 1.444,Å and N—N—C = 113.9°; Kemme et al., 1983; Allen & Kennard, 1993] from (IIa).
The atomic Uij values are moderately well reproduced by a TLS analysis (Schomacher & Trueblood, 1968) [R2 = (ΣΔU2/ΣU2)1/2 = 0.13]; they also pass the Hirshfeld (1976) rigid-bond test; the worst discrepancy is ΔU = 0.0021 (8) Å2 for C4—O1.