Dimethyl 5,6,7-trimeth­oxy-2-methyl-1,2-dihydro­quinoline-2,4-dicarboxyl­ate

Gültekin, Z.; Frey, W.; Hökelek, T.

doi:10.1107/S1600536811004028

Dimethyl 5,6,7-trimethoxy-2-methyl-1,2-dihydroquinoline-2,4-dicarboxylate

In the title compound, C₁₇H₂₁NO₇, the dihydropyridine ring assumes a screw-boat conformation. In the crystal, intermolecular C—H

O hydrogen bonds link the molecules, forming supramolecular chains running along the b axis.

Read article Similar articles

Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536811004028/xu5153sup1.cif Contains datablocks I, global
	Structure factor file (CIF format) https://doi.org/10.1107/S1600536811004028/xu5153Isup2.hkl Contains datablock I

CCDC reference: 815528

checkCIF report

Key indicators

Single-crystal X-ray study
T = 294 K
Mean (C-C) = 0.005 Å
R factor = 0.070
wR factor = 0.156
Data-to-parameter ratio = 14.5

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        C11
PLAT340_ALERT_3_C Low Bond Precision on  C-C Bonds (x 1000) Ang ..          5
PLAT420_ALERT_2_C D-H Without Acceptor       N1     -   H21    ...          ?

Alert level G
PLAT793_ALERT_4_G The Model has Chirality at C1      (Verify) ....          S

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   3 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

Comment top

Dihydroquinolines have been widely studied and found an important structural unit in synthetic organic and medicinal chemistry (Elmore et al., 2001; Dillard et al., 1973; Muren & Weissmann, 1971). Many dihydroquinoline derivatives have been reported in the literature (Edwards et al., 1998; Yan et al., 2004; Petasis & Butkevich, 2009; Gültekin et al., 2010) and some of them have biological effects. For example, 2,2,4-substituted 1,2-dihydroquinolines have been shown antibacterial activities (Johnson et al., 1989).

In the title compound, (I), (Fig. 1), the ring A (C1-C4/C9/N1) is not planar; the puckering parameters (Cremer & Pople, 1975) Q_T = 0.379 (3) Å, ϕ = 21.5 (6)° and θ = 66.4 (5)° suggesting a screw-boat conformation. In the crystal structure, intermolecular C-H···O hydrogen bonds (Table 1) link the molecules to form infinite chains along the b-axis (Fig. 2).

Related literature top

For the preparation of 1,2-dihydroquinoline, see: Edwards et al. (1998); Yan et al. (2004); Petasis & Butkevich (2009); Johnson et al. (1989); Gültekin et al. (2010); Waldmann et al., 2008). For the biological activity of dihydroquinolines, see: Elmore et al. (2001); Dillard et al. (1973); Muren & Weissmann (1971). For ring puckering parameters, see: Cremer & Pople (1975).

Experimental top

The title compound was synthesized by the literature method (Waldmann et al., 2008). 3,4,5-dimethoxyaniline (100 mg, 1 eq) was dissolved in chloroform (1.5 ml) in a screw-capped test tube and Bi(OTf)₃ (5 mol%, 0.05 eq) was added to the mixture. The mixture was stirred at room temperature for 4 h until the starting material was completely consumed as monitored by TLC. The resultant residue was directly purified by flash chromatography on silica (EtOAc:Cylohexane 2:98) gave in 83% yield as a yellow solid. Recrystallized over pentane and ethyl acetate (70:30) gave yellow crystalline solid R_f 0.16 (2:1 Cyclohexane/EtOAc) mp 394-395 K.

Computing details top

Data collection: XSCANS (Siemens, 1996); cell refinement: XSCANS (Siemens, 1996); data reduction: SHELXTL (Sheldrick, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. The molecular structure of the title compound with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. A partial packing diagram viewed down the c-axis. Hydrogen bonds are shown as dashed lines.

Dimethyl 5,6,7-trimethoxy-2-methyl-1,2-dihydroquinoline-2,4-dicarboxylate top

Crystal data top

C₁₇H₂₁NO₇	F(000) = 1488
M_r = 351.35	D_x = 1.330 Mg m⁻³
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 40 reflections
a = 10.476 (2) Å	θ = 10–12°
b = 16.552 (4) Å	µ = 0.10 mm⁻¹
c = 20.238 (4) Å	T = 294 K
V = 3509.2 (13) Å³	Plates, colourless
Z = 8	0.6 × 0.4 × 0.15 mm

Data collection top

Nicolet P3 diffractometer	R_int = 0.000
Radiation source: fine-focus sealed tube	θ_max = 26.0°, θ_min = 2.0°
Graphite monochromator	h = 0→12
Wyckoff scan	k = 0→20
3447 measured reflections	l = 0→24
3447 independent reflections	3 standard reflections every 50 reflections
1839 reflections with I > 2σ(I)	intensity decay: 1%

Refinement top

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)] = 0.070	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.156	w = 1/[σ²(F_o²) + (0.0359P)² + 3.112P] where P = (F_o² + 2F_c²)/3
S = 1.07	(Δ/σ)_max < 0.001
3447 reflections	Δρ_max = 0.18 e Å⁻³
237 parameters	Δρ_min = −0.17 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0031 (3)

Crystal data top

C₁₇H₂₁NO₇	V = 3509.2 (13) Å³
M_r = 351.35	Z = 8
Orthorhombic, Pbca	Mo Kα radiation
a = 10.476 (2) Å	µ = 0.10 mm⁻¹
b = 16.552 (4) Å	T = 294 K
c = 20.238 (4) Å	0.6 × 0.4 × 0.15 mm

Data collection top

Nicolet P3 diffractometer	R_int = 0.000
3447 measured reflections	3 standard reflections every 50 reflections
3447 independent reflections	intensity decay: 1%
1839 reflections with I > 2σ(I)

Refinement top

R[F² > 2σ(F²)] = 0.070	0 restraints
wR(F²) = 0.156	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	Δρ_max = 0.18 e Å⁻³
3447 reflections	Δρ_min = −0.17 e Å⁻³
237 parameters

Special details top

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.

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 > 2sigma(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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.5908 (3)	1.03546 (16)	0.62717 (15)	0.0881 (10)
O2	0.6233 (3)	0.93649 (16)	0.55547 (13)	0.0713 (8)
O3	0.2547 (3)	0.7747 (2)	0.51994 (16)	0.1002 (11)
O4	0.1503 (3)	0.75844 (14)	0.61564 (14)	0.0745 (8)
O5	0.0584 (2)	0.91803 (14)	0.58046 (11)	0.0540 (6)
O6	−0.0366 (2)	1.05816 (15)	0.63970 (12)	0.0637 (7)
O7	0.1046 (3)	1.13852 (16)	0.72647 (13)	0.0736 (8)
N1	0.4420 (3)	0.9400 (2)	0.70665 (15)	0.0590 (9)
H21	0.485 (4)	0.973 (2)	0.733 (2)	0.091 (16)*
C1	0.5191 (3)	0.9018 (2)	0.65584 (19)	0.0525 (9)
C2	0.4333 (3)	0.8467 (2)	0.61660 (18)	0.0536 (9)
H2	0.4696	0.8031	0.5946	0.064*
C3	0.3086 (3)	0.85768 (19)	0.61218 (16)	0.0479 (8)
C4	0.2492 (3)	0.92839 (19)	0.64312 (15)	0.0445 (8)
C5	0.1281 (3)	0.9578 (2)	0.62794 (16)	0.0457 (8)
C6	0.0824 (3)	1.0285 (2)	0.65599 (17)	0.0489 (9)
C7	0.1567 (3)	1.0694 (2)	0.70186 (17)	0.0541 (9)
C8	0.2776 (3)	1.0412 (2)	0.71861 (17)	0.0566 (10)
H8	0.3272	1.0688	0.7493	0.068*
C9	0.3233 (3)	0.9712 (2)	0.68871 (16)	0.0489 (9)
C10	0.6265 (4)	0.8538 (2)	0.6884 (2)	0.0730 (12)
H10A	0.6801	0.8899	0.7132	0.109*
H10B	0.6763	0.8274	0.6550	0.109*
H10C	0.5907	0.8141	0.7176	0.109*
C11	0.5798 (3)	0.9663 (2)	0.61161 (19)	0.0528 (9)
C12	0.6849 (5)	0.9931 (3)	0.5108 (2)	0.1013 (16)
H12A	0.6974	0.9678	0.4686	0.152*
H12B	0.7660	1.0088	0.5287	0.152*
H12C	0.6319	1.0400	0.5055	0.152*
C13	0.2345 (4)	0.7940 (2)	0.5758 (2)	0.0613 (10)
C14	0.0782 (5)	0.6925 (3)	0.5864 (3)	0.118 (2)
H14A	0.0260	0.6676	0.6197	0.177*
H14B	0.1362	0.6532	0.5686	0.177*
H14C	0.0249	0.7130	0.5517	0.177*
C15	−0.0622 (3)	0.8868 (2)	0.6031 (2)	0.0755 (12)
H15A	−0.1022	0.8569	0.5682	0.113*
H15B	−0.1164	0.9308	0.6160	0.113*
H15C	−0.0483	0.8519	0.6403	0.113*
C16	−0.0349 (5)	1.1165 (3)	0.5882 (2)	0.0906 (15)
H16A	−0.1179	1.1406	0.5842	0.136*
H16B	−0.0124	1.0907	0.5474	0.136*
H16C	0.0268	1.1576	0.5984	0.136*
C17	0.1819 (4)	1.1883 (2)	0.7671 (2)	0.0896 (15)
H17A	0.1360	1.2367	0.7781	0.134*
H17B	0.2587	1.2022	0.7438	0.134*
H17C	0.2033	1.1597	0.8069	0.134*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.111 (3)	0.0508 (17)	0.103 (2)	−0.0080 (17)	0.014 (2)	0.0001 (16)
O2	0.0779 (19)	0.0685 (17)	0.0676 (18)	−0.0126 (15)	0.0092 (15)	−0.0002 (15)
O3	0.101 (2)	0.115 (3)	0.085 (2)	−0.028 (2)	0.012 (2)	−0.047 (2)
O4	0.0813 (18)	0.0507 (15)	0.092 (2)	−0.0248 (15)	−0.0035 (17)	−0.0025 (15)
O5	0.0507 (14)	0.0598 (15)	0.0516 (14)	−0.0123 (12)	−0.0065 (12)	−0.0034 (12)
O6	0.0493 (15)	0.0704 (17)	0.0712 (18)	0.0042 (13)	0.0024 (13)	−0.0002 (14)
O7	0.0750 (19)	0.0670 (17)	0.0789 (19)	0.0009 (15)	0.0051 (15)	−0.0253 (15)
N1	0.0520 (19)	0.073 (2)	0.0524 (19)	−0.0034 (18)	−0.0093 (16)	−0.0077 (17)
C1	0.050 (2)	0.048 (2)	0.060 (2)	0.0010 (18)	−0.0078 (18)	0.0047 (18)
C2	0.056 (2)	0.0443 (19)	0.060 (2)	0.0016 (18)	−0.0018 (19)	0.0009 (17)
C3	0.055 (2)	0.0426 (19)	0.046 (2)	−0.0088 (17)	−0.0019 (17)	0.0038 (16)
C4	0.0478 (18)	0.0465 (18)	0.0391 (17)	−0.0091 (17)	0.0019 (16)	−0.0005 (16)
C5	0.0453 (19)	0.052 (2)	0.0395 (18)	−0.0142 (17)	−0.0014 (16)	−0.0009 (16)
C6	0.0425 (19)	0.053 (2)	0.051 (2)	−0.0064 (17)	0.0045 (17)	−0.0020 (17)
C7	0.055 (2)	0.052 (2)	0.055 (2)	−0.0057 (19)	0.0102 (19)	−0.0077 (18)
C8	0.058 (2)	0.063 (2)	0.049 (2)	−0.013 (2)	0.0029 (18)	−0.0144 (19)
C9	0.047 (2)	0.056 (2)	0.043 (2)	−0.0094 (18)	−0.0022 (17)	0.0025 (17)
C10	0.064 (2)	0.069 (3)	0.086 (3)	0.003 (2)	−0.017 (2)	0.020 (2)
C11	0.045 (2)	0.050 (2)	0.063 (2)	0.0026 (18)	−0.0061 (19)	0.0045 (19)
C12	0.104 (4)	0.115 (4)	0.085 (3)	−0.029 (3)	0.017 (3)	0.027 (3)
C13	0.060 (2)	0.054 (2)	0.070 (3)	−0.008 (2)	−0.001 (2)	−0.009 (2)
C14	0.106 (4)	0.072 (3)	0.176 (6)	−0.041 (3)	−0.005 (4)	−0.029 (3)
C15	0.050 (2)	0.075 (3)	0.102 (3)	−0.016 (2)	−0.006 (2)	−0.009 (2)
C16	0.094 (3)	0.072 (3)	0.106 (4)	0.006 (3)	−0.017 (3)	0.021 (3)
C17	0.104 (4)	0.073 (3)	0.092 (4)	−0.006 (3)	0.000 (3)	−0.038 (3)

Geometric parameters (Å, º) top

O1—C11	1.193 (4)	C5—C6	1.386 (5)
O2—C11	1.320 (4)	C6—C7	1.387 (5)
O2—C12	1.453 (5)	C7—C8	1.391 (5)
O3—C13	1.194 (4)	C8—C9	1.393 (5)
O4—C13	1.332 (4)	C8—H8	0.9300
O4—C14	1.453 (5)	C10—H10A	0.9600
O5—C5	1.374 (4)	C10—H10B	0.9600
O5—C15	1.440 (4)	C10—H10C	0.9600
O6—C6	1.380 (4)	C12—H12A	0.9600
O6—C16	1.421 (5)	C12—H12B	0.9600
O7—C7	1.362 (4)	C12—H12C	0.9600
O7—C17	1.418 (4)	C14—H14A	0.9600
N1—C1	1.453 (4)	C14—H14B	0.9600
N1—C9	1.394 (4)	C14—H14C	0.9600
N1—H21	0.89 (4)	C15—H15A	0.9600
C1—C2	1.507 (5)	C15—H15B	0.9600
C1—C10	1.527 (5)	C15—H15C	0.9600
C1—C11	1.532 (5)	C16—H16A	0.9600
C2—C3	1.322 (4)	C16—H16B	0.9600
C2—H2	0.9300	C16—H16C	0.9600
C3—C4	1.466 (5)	C17—H17A	0.9600
C3—C13	1.502 (5)	C17—H17B	0.9600
C4—C5	1.393 (5)	C17—H17C	0.9600
C4—C9	1.399 (4)

C11—O2—C12	116.6 (3)	C1—C10—H10C	109.5
C13—O4—C14	115.5 (4)	H10A—C10—H10B	109.5
C5—O5—C15	114.5 (3)	H10A—C10—H10C	109.5
C6—O6—C16	113.9 (3)	H10B—C10—H10C	109.5
C7—O7—C17	118.1 (3)	O1—C11—O2	123.6 (4)
C1—N1—H21	114 (3)	O1—C11—C1	123.7 (4)
C9—N1—C1	118.2 (3)	O2—C11—C1	112.7 (3)
C9—N1—H21	112 (3)	O2—C12—H12A	109.5
N1—C1—C2	107.7 (3)	O2—C12—H12B	109.5
N1—C1—C10	109.3 (3)	O2—C12—H12C	109.5
N1—C1—C11	109.9 (3)	H12A—C12—H12B	109.5
C2—C1—C10	110.7 (3)	H12A—C12—H12C	109.5
C2—C1—C11	111.2 (3)	H12B—C12—H12C	109.5
C10—C1—C11	108.0 (3)	O3—C13—O4	124.9 (4)
C1—C2—H2	118.6	O3—C13—C3	124.1 (4)
C3—C2—C1	122.8 (3)	O4—C13—C3	110.9 (3)
C3—C2—H2	118.6	O4—C14—H14A	109.5
C2—C3—C4	120.1 (3)	O4—C14—H14B	109.5
C2—C3—C13	116.6 (3)	O4—C14—H14C	109.5
C4—C3—C13	123.4 (3)	H14A—C14—H14B	109.5
C5—C4—C3	124.9 (3)	H14A—C14—H14C	109.5
C5—C4—C9	118.3 (3)	H14B—C14—H14C	109.5
C9—C4—C3	116.7 (3)	O5—C15—H15A	109.5
O5—C5—C4	118.1 (3)	O5—C15—H15B	109.5
O5—C5—C6	120.5 (3)	O5—C15—H15C	109.5
C6—C5—C4	121.3 (3)	H15A—C15—H15B	109.5
O6—C6—C5	120.9 (3)	H15A—C15—H15C	109.5
O6—C6—C7	119.6 (3)	H15B—C15—H15C	109.5
C5—C6—C7	119.5 (3)	O6—C16—H16A	109.5
O7—C7—C6	115.4 (3)	O6—C16—H16B	109.5
O7—C7—C8	123.9 (3)	O6—C16—H16C	109.5
C6—C7—C8	120.7 (3)	H16A—C16—H16B	109.5
C7—C8—C9	119.1 (3)	H16A—C16—H16C	109.5
C7—C8—H8	120.5	H16B—C16—H16C	109.5
C9—C8—H8	120.5	O7—C17—H17A	109.5
N1—C9—C4	118.7 (3)	O7—C17—H17B	109.5
C8—C9—N1	120.1 (3)	O7—C17—H17C	109.5
C8—C9—C4	121.1 (3)	H17A—C17—H17B	109.5
C1—C10—H10A	109.5	H17A—C17—H17C	109.5
C1—C10—H10B	109.5	H17B—C17—H17C	109.5

C12—O2—C11—O1	−1.3 (6)	C2—C3—C4—C9	−14.3 (5)
C12—O2—C11—C1	−178.8 (3)	C13—C3—C4—C5	−19.0 (5)
C14—O4—C13—O3	−1.0 (6)	C13—C3—C4—C9	164.4 (3)
C14—O4—C13—C3	−176.6 (3)	C2—C3—C13—O3	−57.5 (6)
C15—O5—C5—C4	120.6 (3)	C2—C3—C13—O4	118.1 (4)
C15—O5—C5—C6	−64.2 (4)	C4—C3—C13—O3	123.8 (5)
C16—O6—C6—C5	−94.5 (4)	C4—C3—C13—O4	−60.6 (4)
C16—O6—C6—C7	86.5 (4)	C3—C4—C5—O5	−0.1 (5)
C17—O7—C7—C6	−172.3 (3)	C3—C4—C5—C6	−175.2 (3)
C17—O7—C7—C8	5.6 (5)	C9—C4—C5—O5	176.5 (3)
C9—N1—C1—C2	−45.4 (4)	C9—C4—C5—C6	1.3 (5)
C9—N1—C1—C10	−165.7 (3)	C3—C4—C9—N1	−6.3 (4)
C9—N1—C1—C11	76.0 (4)	C3—C4—C9—C8	177.2 (3)
C1—N1—C9—C8	−145.0 (3)	C5—C4—C9—N1	176.8 (3)
C1—N1—C9—C4	38.5 (5)	C5—C4—C9—C8	0.3 (5)
N1—C1—C2—C3	24.7 (5)	O5—C5—C6—O6	3.6 (5)
C10—C1—C2—C3	144.2 (4)	O5—C5—C6—C7	−177.4 (3)
C11—C1—C2—C3	−95.8 (4)	C4—C5—C6—O6	178.7 (3)
N1—C1—C11—O1	18.8 (5)	C4—C5—C6—C7	−2.3 (5)
N1—C1—C11—O2	−163.7 (3)	C5—C6—C7—O7	179.6 (3)
C2—C1—C11—O1	138.0 (4)	C5—C6—C7—C8	1.7 (5)
C2—C1—C11—O2	−44.5 (4)	O6—C6—C7—O7	−1.4 (5)
C10—C1—C11—O1	−100.4 (4)	O6—C6—C7—C8	−179.3 (3)
C10—C1—C11—O2	77.1 (4)	O7—C7—C8—C9	−177.8 (3)
C1—C2—C3—C4	3.5 (5)	C6—C7—C8—C9	0.0 (5)
C1—C2—C3—C13	−175.2 (3)	C7—C8—C9—N1	−177.4 (3)
C2—C3—C4—C5	162.3 (3)	C7—C8—C9—C4	−1.0 (5)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C14—H14A···O1ⁱ	0.96	2.51	3.251 (6)	134

Symmetry code: (i) −x+1/2, y−1/2, z.

Experimental details

Crystal data
Chemical formula	C₁₇H₂₁NO₇
M_r	351.35
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	294
a, b, c (Å)	10.476 (2), 16.552 (4), 20.238 (4)
V (Å³)	3509.2 (13)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.6 × 0.4 × 0.15

Data collection
Diffractometer	Nicolet P3 diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	3447, 3447, 1839
R_int	0.000
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.070, 0.156, 1.07
No. of reflections	3447
No. of parameters	237
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.18, −0.17

Computer programs: XSCANS (Siemens, 1996), SHELXTL (Sheldrick, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).