Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536803001624/na6197sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536803001624/na6197Isup2.hkl |
CCDC reference: 204715
Key indicators
- Single-crystal X-ray study
- T = 293 K
- Mean (C-C) = 0.004 Å
- R factor = 0.067
- wR factor = 0.219
- Data-to-parameter ratio = 14.0
checkCIF results
No syntax errors found ADDSYM reports no extra symmetry
Alert Level B:
SHFSU_01 Alert B The absolute value of parameter shift to su ratio > 0.10 Absolute value of the parameter shift to su ratio given 0.110 Additional refinement cycles may be required.
Alert Level C:
DIFMX_01 Alert C The maximum difference density is > 0.1*ZMAX*0.75 _refine_diff_density_max given = 0.620 Test value = 0.600 DIFMX_02 Alert C The minimum difference density is > 0.1*ZMAX*0.75 The relevant atom site should be identified. RADNW_01 Alert C The radiation wavelength lies outside the expected range for the supplied radiation type. Expected range 1.54175-1.54180 Wavelength given = 1.54184 REFLT_03 From the CIF: _diffrn_reflns_theta_max 69.11 From the CIF: _reflns_number_total 2962 TEST2: Reflns within _diffrn_reflns_theta_max Count of symmetry unique reflns 3172 Completeness (_total/calc) 93.38% Alert C: < 95% complete WEIGH_01 Alert C Extra text has been found in the _refine_ls_weighting_scheme field. This should be in the _refine_ls_weighting_details field. Weighting scheme given as calc' Weighting scheme identified as calc PLAT_360 Alert C Short C(sp3)-C(sp3) Bond C(33) - C(34) = 1.41 Ang.
0 Alert Level A = Potentially serious problem
1 Alert Level B = Potential problem
6 Alert Level C = Please check
The title compund was prepared by stirring a solution of 5-ethoxycarbonyl-6-methyl-4-phenyl-3,4-dihydro-2(1H)-pyridone (10 mmol) in anhydrous N,N-dimethylformamide (40 mmol), and phosphorus oxychloride (40 mmol) in dry chloroform (50 ml). After stirring at room temperature for 18 h, 20 ml of anhydrous ethanol was added. After 0.5 h, a white solid had precipitated and was filtered off. Further purification was accomplished by recrystallization from methanol (yield 68%; m.p. 746–747 K). IR (KBr, cm−1): 3202 (NH), 1697 (C═O), 1674 (C═O), 1637 (C═C); 1H NMR (DMSO-δ6, p.p.m.): 9.68 (s, 1H, NH), 7.36 (s, 1H, ═CH), 7.31–7.11 (m, 5H, Ph), 4.89 (s, 1H, H-4), 4.13 (q, 2H, CH2), 3.96 (q, 2H, CH2), 2.29 (s, 3H, CH3), 1.22 (t, 3H, CH3), 1.06 (t, 3H, CH3); 13C NMR (DMSO-δ6, p.p.m.): 171.4 (C2), 169.7 (COO), 161.2 (═CH), 152.2 (C6), 149.5 (C1'), 133.4 (C2', C6'), 131.9 (C3', C5'), 131.4 (C4'), 114.5 (C3), 109.2 (C5), 75.3 (CH2), 64.5 (CH2), 43.4 (C4), 23.5 (CH3), 20.5 (CH3), 19.3 (CH3); MS: m/Z (intensity%): 315 (M+, 64), 286 (60), 270 (31), 238 (65), 210 (100), 182 (44). Crystals suitable for X-ray analysis were obtained by slow evaporation from methanol.
H atoms were calculated geometrically and included in the refinement, but were restrained to ride on their parent atoms. The isotropic displacement parameters of the H atoms were fixed at 1.3Ueq of their parent atoms.
Data collection: XSCANS (Siemens, 1996); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Bergerhoff, 1996); software used to prepare material for publication: PLATON (Spek, 1990), PARST (Nardelli, 1995) and PARSTCIF (Nardelli, 1991).
Fig. 1. Plot showing the atomic numbering scheme in (I). Displacement ellipsoids are drawn at 50% probability level for non-H atoms. |
C18H21NO4 | F(000) = 1344 |
Mr = 315.36 | Dx = 1.230 Mg m−3 |
Monoclinic, C2/c | Cu Kα radiation, λ = 1.54184 Å |
a = 22.652 (1) Å | Cell parameters from 40 reflections |
b = 10.5508 (3) Å | θ = 10.8–27.9° |
c = 15.7162 (7) Å | µ = 0.71 mm−1 |
β = 114.921 (4)° | T = 293 K |
V = 3406.4 (3) Å3 | Prism, colourless |
Z = 8 | 0.60 × 0.40 × 0.40 mm |
Siemens P4 four-circle diffractometer | Rint = 0.030 |
ω/2θ scans | θmax = 69.1° |
Absorption correction: ψ scan (North et al., 1968) | h = −1→27 |
Tmin = 0.565, Tmax = 0.753 | k = −1→12 |
7611 measured reflections | l = −19→17 |
2962 independent reflections | 3 standard reflections every 100 reflections |
2690 reflections with F2 > 2σ(F2) | intensity decay: 0.0% |
Refinement on F2 | H-atom parameters constrained |
Least-squares matrix: full | Calculated' w = 1/[σ2(Fo2) + (0.1525P)2 + 3.0912P] where P = (Fo2 + 2Fc2)/3 |
R[F2 > 2σ(F2)] = 0.067 | (Δ/σ)max = 0.110 |
wR(F2) = 0.219 | Δρmax = 0.62 e Å−3 |
S = 0.98 | Δρmin = −0.39 e Å−3 |
2962 reflections | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin((2θ)]-1/4 |
212 parameters | Extinction coefficient: 0.0018 (3) |
C18H21NO4 | V = 3406.4 (3) Å3 |
Mr = 315.36 | Z = 8 |
Monoclinic, C2/c | Cu Kα radiation |
a = 22.652 (1) Å | µ = 0.71 mm−1 |
b = 10.5508 (3) Å | T = 293 K |
c = 15.7162 (7) Å | 0.60 × 0.40 × 0.40 mm |
β = 114.921 (4)° |
Siemens P4 four-circle diffractometer | 2690 reflections with F2 > 2σ(F2) |
Absorption correction: ψ scan (North et al., 1968) | Rint = 0.030 |
Tmin = 0.565, Tmax = 0.753 | 3 standard reflections every 100 reflections |
7611 measured reflections | intensity decay: 0.0% |
2962 independent reflections |
R[F2 > 2σ(F2)] = 0.067 | H-atom parameters constrained |
wR(F2) = 0.219 | (Δ/σ)max = 0.110 |
S = 0.98 | Δρmax = 0.62 e Å−3 |
2962 reflections | Δρmin = −0.39 e Å−3 |
212 parameters |
Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All e.s.d.'s are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles |
x | y | z | Uiso*/Ueq | ||
N1 | 0.04183 (9) | 0.4236 (2) | 0.11740 (10) | 0.0497 (7)* | |
C2 | 0.00800 (10) | 0.3230 (2) | 0.0642 (2) | 0.0458 (8)* | |
O21 | −0.02680 (9) | 0.3385 (2) | −0.02010 (10) | 0.0600 (7)* | |
C3 | 0.01580 (10) | 0.2040 (2) | 0.11450 (10) | 0.0418 (7)* | |
C31 | −0.02890 (10) | 0.1150 (2) | 0.0729 (2) | 0.0468 (8)* | |
O32 | −0.02744 (8) | 0.0026 (2) | 0.11370 (10) | 0.0567 (7)* | |
C33 | −0.0839 (2) | −0.0762 (3) | 0.0651 (2) | 0.0790 (10)* | |
C34 | −0.0779 (3) | −0.1899 (4) | 0.1154 (3) | 0.120 (3)* | |
C4 | 0.07280 (10) | 0.1869 (2) | 0.20980 (10) | 0.0406 (8)* | |
C1' | 0.12890 (10) | 0.1215 (2) | 0.19700 (10) | 0.0426 (8)* | |
C2' | 0.13090 (10) | −0.0103 (2) | 0.1940 (2) | 0.0574 (9)* | |
C3' | 0.1789 (2) | −0.0711 (3) | 0.1768 (2) | 0.0720 (10)* | |
C4' | 0.22530 (10) | −0.0025 (3) | 0.1627 (2) | 0.0750 (10)* | |
C5' | 0.22430 (10) | 0.1273 (3) | 0.1663 (2) | 0.0700 (10)* | |
C6' | 0.17630 (10) | 0.1893 (2) | 0.1833 (2) | 0.0550 (10)* | |
C5 | 0.09230 (10) | 0.3116 (2) | 0.26190 (10) | 0.0410 (8)* | |
C51 | 0.13120 (10) | 0.2965 (2) | 0.3636 (2) | 0.0447 (8)* | |
O52 | 0.15067 (9) | 0.1948 (2) | 0.39910 (10) | 0.0612 (7)* | |
O53 | 0.14382 (9) | 0.4028 (2) | 0.41410 (10) | 0.0619 (7)* | |
C54 | 0.1836 (2) | 0.3895 (3) | 0.5142 (2) | 0.0730 (10)* | |
C55 | 0.1992 (3) | 0.5173 (4) | 0.5544 (2) | 0.127 (2)* | |
C6 | 0.07680 (10) | 0.4228 (2) | 0.2147 (2) | 0.0443 (8)* | |
C61 | 0.09320 (10) | 0.5550 (2) | 0.2530 (2) | 0.0640 (10)* | |
H1 | 0.0415 | 0.493 | 0.0885 | 0.06* | |
H31 | −0.062 | 0.1312 | 0.014 | 0.056* | |
H33A | −0.1229 | −0.0314 | 0.0591 | 0.095* | |
H33B | −0.0878 | −0.0953 | 0.0026 | 0.095* | |
H34A | −0.0355 | −0.2257 | 0.1318 | 0.18* | |
H34B | −0.1106 | −0.2489 | 0.0772 | 0.18* | |
H34C | −0.0835 | −0.1725 | 0.1715 | 0.18* | |
H4 | 0.0586 | 0.1302 | 0.2469 | 0.049* | |
H2' | 0.0997 | −0.0579 | 0.2037 | 0.069* | |
H3' | 0.1797 | −0.1592 | 0.1748 | 0.086* | |
H4' | 0.2573 | −0.0436 | 0.1506 | 0.09* | |
H5' | 0.256 | 0.1741 | 0.1574 | 0.084* | |
H6' | 0.1761 | 0.2774 | 0.1855 | 0.066* | |
H54A | 0.2232 | 0.3437 | 0.5251 | 0.088* | |
H54B | 0.16 | 0.3429 | 0.5432 | 0.088* | |
H55A | 0.2308 | 0.5117 | 0.6184 | 0.153* | |
H55B | 0.1604 | 0.5569 | 0.552 | 0.153* | |
H55C | 0.2166 | 0.5667 | 0.519 | 0.153* | |
H61A | 0.1005 | 0.6075 | 0.2084 | 0.095* | |
H61B | 0.1318 | 0.5532 | 0.3108 | 0.095* | |
H61C | 0.0578 | 0.5888 | 0.2641 | 0.095* |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0500 (10) | 0.0430 (10) | 0.0420 (10) | −0.0014 (8) | 0.0049 (8) | 0.0041 (7) |
C2 | 0.0390 (10) | 0.0490 (10) | 0.0380 (10) | 0.0027 (9) | 0.0062 (9) | 0.0015 (9) |
O21 | 0.0620 (10) | 0.0553 (9) | 0.0401 (8) | −0.0021 (8) | −0.0010 (7) | 0.0049 (7) |
C3 | 0.0330 (10) | 0.0450 (10) | 0.0390 (10) | 0.0009 (9) | 0.0070 (8) | 0.0009 (8) |
C31 | 0.0410 (10) | 0.0500 (10) | 0.0390 (10) | −0.0010 (10) | 0.0064 (9) | 0.0021 (9) |
O32 | 0.0510 (10) | 0.0540 (10) | 0.0475 (9) | −0.0142 (8) | 0.0034 (7) | −0.0008 (7) |
C33 | 0.083 (2) | 0.071 (2) | 0.063 (2) | −0.036 (2) | 0.0090 (10) | −0.0040 (10) |
C34 | 0.167 (5) | 0.087 (3) | 0.091 (3) | −0.054 (3) | 0.038 (3) | 0.002 (2) |
C4 | 0.0340 (10) | 0.0430 (10) | 0.0360 (10) | −0.0022 (8) | 0.0069 (8) | 0.0017 (8) |
C1' | 0.0360 (10) | 0.0450 (10) | 0.0350 (10) | 0.0058 (9) | 0.0032 (8) | 0.0019 (8) |
C2' | 0.055 (2) | 0.0460 (10) | 0.0580 (10) | 0.0060 (10) | 0.0110 (10) | 0.0020 (10) |
C3' | 0.070 (2) | 0.057 (2) | 0.068 (2) | 0.0240 (10) | 0.0090 (10) | −0.0050 (10) |
C4' | 0.054 (2) | 0.089 (2) | 0.072 (2) | 0.026 (2) | 0.0160 (10) | −0.011 (2) |
C5' | 0.047 (2) | 0.085 (2) | 0.077 (2) | 0.0050 (10) | 0.0250 (10) | −0.005 (2) |
C6' | 0.0430 (10) | 0.0550 (10) | 0.0620 (10) | 0.0010 (10) | 0.0180 (10) | −0.0030 (10) |
C5 | 0.0310 (10) | 0.0470 (10) | 0.0380 (10) | 0.0014 (8) | 0.0085 (9) | −0.0016 (8) |
C51 | 0.0330 (10) | 0.0540 (10) | 0.0400 (10) | 0.0000 (9) | 0.0085 (9) | −0.0013 (9) |
O52 | 0.0590 (10) | 0.0580 (10) | 0.0456 (9) | 0.0050 (8) | 0.0023 (8) | 0.0063 (7) |
O53 | 0.0680 (10) | 0.0610 (10) | 0.0378 (8) | 0.0027 (9) | 0.0044 (7) | −0.0066 (7) |
C54 | 0.077 (2) | 0.079 (2) | 0.0380 (10) | 0.004 (2) | 0.0000 (10) | −0.0050 (10) |
C55 | 0.171 (4) | 0.102 (3) | 0.054 (2) | 0.007 (3) | −0.006 (2) | −0.025 (2) |
C6 | 0.0340 (10) | 0.0460 (10) | 0.0430 (10) | 0.0018 (9) | 0.0065 (9) | −0.0029 (8) |
C61 | 0.061 (2) | 0.0450 (10) | 0.0580 (10) | 0.0070 (10) | 0.0000 (10) | −0.0060 (10) |
O21—C2 | 1.234 (3) | C33—C34 | 1.411 (5) |
O32—C31 | 1.342 (3) | C54—C55 | 1.468 (5) |
O32—C33 | 1.445 (4) | C2'—H2' | 0.93 |
O52—C51 | 1.204 (3) | C3'—H3' | 0.93 |
O53—C51 | 1.333 (3) | C4—H4 | 0.98 |
O53—C54 | 1.453 (3) | C4'—H4' | 0.93 |
N1—C2 | 1.368 (3) | C5'—H5' | 0.93 |
N1—C6 | 1.394 (3) | C6'—H6' | 0.93 |
N1—H1 | 0.86 | C31—H31 | 0.93 |
C1'—C2' | 1.393 (3) | C33—H33A | 0.97 |
C1'—C6' | 1.380 (4) | C33—H33B | 0.97 |
C1'—C4 | 1.531 (3) | C34—H34A | 0.96 |
C2—C3 | 1.454 (3) | C34—H34B | 0.96 |
C2'—C3' | 1.385 (5) | C34—H34C | 0.96 |
C3—C4 | 1.522 (3) | C54—H54A | 0.97 |
C3—C31 | 1.332 (3) | C54—H54B | 0.97 |
C3'—C4' | 1.369 (5) | C55—H55A | 0.96 |
C4—C5 | 1.514 (3) | C55—H55B | 0.96 |
C4'—C5' | 1.371 (4) | C55—H55C | 0.96 |
C5—C51 | 1.473 (3) | C61—H61A | 0.96 |
C5—C6 | 1.353 (3) | C61—H61B | 0.96 |
C5'—C6' | 1.388 (4) | C61—H61C | 0.96 |
C6—C61 | 1.502 (3) | ||
C31—O32—C33 | 114.7 (2) | C3—C4—H4 | 108 |
C51—O53—C54 | 116.3 (2) | C5—C4—H4 | 108 |
C2—N1—C6 | 125.4 (2) | C3'—C4'—H4' | 120 |
C6—N1—H1 | 117 | C5'—C4'—H4' | 120 |
C2—N1—H1 | 117 | C4'—C5'—H5' | 120 |
C4—C1'—C6' | 122.0 (2) | C6'—C5'—H5' | 120 |
C2'—C1'—C6' | 118.3 (2) | C1'—C6'—H6' | 120 |
C2'—C1'—C4 | 119.6 (2) | C5'—C6'—H6' | 120 |
O21—C2—N1 | 119.6 (2) | O32—C31—H31 | 119 |
O21—C2—C3 | 125.0 (2) | C3—C31—H31 | 119 |
N1—C2—C3 | 115.4 (2) | O32—C33—H33A | 110 |
C1'—C2'—C3' | 120.6 (3) | O32—C33—H33B | 110 |
C4—C3—C31 | 123.6 (2) | C34—C33—H33A | 110 |
C2—C3—C4 | 119.7 (2) | C34—C33—H33B | 110 |
C2—C3—C31 | 116.7 (2) | H33A—C33—H33B | 108 |
C2'—C3'—C4' | 120.5 (3) | C33—C34—H34A | 110 |
C3—C4—C5 | 111.2 (2) | C33—C34—H34B | 110 |
C1'—C4—C3 | 109.3 (2) | C33—C34—H34C | 110 |
C1'—C4—C5 | 113.2 (2) | H34A—C34—H34B | 110 |
C3'—C4'—C5' | 119.6 (3) | H34A—C34—H34C | 110 |
C6—C5—C51 | 126.0 (2) | H34B—C34—H34C | 109 |
C4—C5—C51 | 113.4 (2) | O53—C54—H54A | 110 |
C4—C5—C6 | 120.5 (2) | O53—C54—H54B | 110 |
C4'—C5'—C6' | 120.5 (3) | C55—C54—H54A | 110 |
C5—C6—C61 | 128.5 (2) | C55—C54—H54B | 110 |
N1—C6—C5 | 120.2 (2) | H54A—C54—H54B | 108 |
N1—C6—C61 | 111.3 (2) | C54—C55—H55A | 110 |
C1'—C6'—C5' | 120.6 (2) | C54—C55—H55B | 109 |
O32—C31—C3 | 121.9 (2) | C54—C55—H55C | 109 |
O32—C33—C34 | 109.8 (3) | H55A—C55—H55B | 110 |
O52—C51—O53 | 122.0 (2) | H55A—C55—H55C | 110 |
O52—C51—C5 | 122.3 (2) | H55B—C55—H55C | 110 |
O53—C51—C5 | 115.8 (2) | C6—C61—H61A | 110 |
O53—C54—C55 | 107.7 (2) | C6—C61—H61B | 110 |
C1'—C2'—H2' | 120 | C6—C61—H61C | 110 |
C3'—C2'—H2' | 120 | H61A—C61—H61B | 110 |
C2'—C3'—H3' | 120 | H61A—C61—H61C | 110 |
C4'—C3'—H3' | 120 | H61B—C61—H61C | 110 |
C1'—C4—H4 | 108 |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O21i | 0.86 | 2.03 | 2.885 (3) | 171 |
C31—H31···O21 | 0.93 | 2.46 | 2.785 (3) | 100 |
C61—H61B···O53 | 0.96 | 2.20 | 2.803 (3) | 119 |
Symmetry code: (i) −x, −y+1, −z. |
Experimental details
Crystal data | |
Chemical formula | C18H21NO4 |
Mr | 315.36 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 293 |
a, b, c (Å) | 22.652 (1), 10.5508 (3), 15.7162 (7) |
β (°) | 114.921 (4) |
V (Å3) | 3406.4 (3) |
Z | 8 |
Radiation type | Cu Kα |
µ (mm−1) | 0.71 |
Crystal size (mm) | 0.60 × 0.40 × 0.40 |
Data collection | |
Diffractometer | Siemens P4 four-circle diffractometer |
Absorption correction | ψ scan (North et al., 1968) |
Tmin, Tmax | 0.565, 0.753 |
No. of measured, independent and observed [F2 > 2σ(F2)] reflections | 7611, 2962, 2690 |
Rint | 0.030 |
(sin θ/λ)max (Å−1) | 0.606 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.067, 0.219, 0.98 |
No. of reflections | 2962 |
No. of parameters | 212 |
No. of restraints | ? |
H-atom treatment | H-atom parameters constrained |
(Δ/σ)max | 0.110 |
Δρmax, Δρmin (e Å−3) | 0.62, −0.39 |
Computer programs: XSCANS (Siemens, 1996), XSCANS, SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 1997), DIAMOND (Bergerhoff, 1996), PLATON (Spek, 1990), PARST (Nardelli, 1995) and PARSTCIF (Nardelli, 1991).
O21—C2 | 1.234 (3) | O53—C51 | 1.333 (3) |
O32—C31 | 1.342 (3) | O53—C54 | 1.453 (3) |
O32—C33 | 1.445 (4) | N1—C2 | 1.368 (3) |
O52—C51 | 1.204 (3) | N1—C6 | 1.394 (3) |
C31—O32—C33 | 114.7 (2) | N1—C6—C61 | 111.3 (2) |
C51—O53—C54 | 116.3 (2) | O32—C31—C3 | 121.9 (2) |
C2—N1—C6 | 125.4 (2) | O32—C33—C34 | 109.8 (3) |
O21—C2—N1 | 119.6 (2) | O52—C51—O53 | 122.0 (2) |
O21—C2—C3 | 125.0 (2) | O52—C51—C5 | 122.3 (2) |
N1—C2—C3 | 115.4 (2) | O53—C51—C5 | 115.8 (2) |
N1—C6—C5 | 120.2 (2) | O53—C54—C55 | 107.7 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O21i | 0.86 | 2.03 | 2.885 (3) | 171 |
C31—H31···O21 | 0.93 | 2.46 | 2.785 (3) | 100 |
C61—H61B···O53 | 0.96 | 2.20 | 2.803 (3) | 119 |
Symmetry code: (i) −x, −y+1, −z. |
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A wide variety of compounds containing the 2(1H)-pyridone ring are found in nature and in some cases they diplay useful biological properties (Overman et al., 1980). 2(1H)-Pyridones are very close in structure to the 1,4-dihidropyridines, which have been used as effective drugs in the treatment of cardiovascular diseases. In a previous work, we have reported a general procedure (Verdecia et al., 1996) for the synthesis of novel o-chloroformyl-substituted ethyl 1,4-dihydropyridine-5-carboxylates from the corresponding 3,4-dihydropyridone (Goldmann & Stoltefuss, 1991). The reaction proceeds through a mechanism involving several steps and one of the intermediate formed in the reaction is the title compound, (I).
The 2(1H)-pyridone ring of (I) has a screw–boat conformation, with puckering parameters (Cremer & Pople, 1975) Q = 0.280 (2) Å, θ = 109.5 (4)° and ϕ = 339.1 (5)°, with the axis through C2—C3, for N1—C1—C2—C3—C4—C5—C6. The dihedral angle between the least-squares planes of the phenyl ring and the pyridone moiety is 86.0 (1)°. The mean Csp2—Csp2 bond length within this ring is 1.434 (1) Å. An N—H···O hydrogen bond holds the molecules together in a dimeric association (Table 2).