Iso­propyl 2-methyl-4-(3-nitro­phenyl)-5,7-dioxo-4,5,6,7-tetra­hydro-1H-pyrrolo­[3,4-b]­pyridine-3-carboxyl­ate

The crystal structure of the title compound, C₁₈H₁₇N₃O₆, is formed by single mol­ecules linked by N—H...O hydrogen bonds into planar sheets. The dihedral angle between the mean planes of the pyridine and substituted phenyl rings is 84.2 (1)°. The 3-nitro substituent on the phenyl ring is rotated from coplanarity with the ring by only 3.7 (2)°.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.060
• wR factor = 0.083
• Data-to-parameter ratio = 16.6

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT026_ALERT_3_B Ratio Observed / Unique Reflections too Low ....         35 Perc.
PLAT029_ALERT_3_B _diffrn_measured_fraction_theta_full Low .......       0.98
PLAT230_ALERT_2_B Hirshfeld Test Diff for    C43    -   C44      =       7.42 su

Alert level C
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       2.79 Ratio
PLAT220_ALERT_2_C Large Non-Solvent    O     Ueq(max)/Ueq(min) ...       2.53 Ratio
PLAT222_ALERT_3_C Large Non-Solvent    H     Ueq(max)/Ueq(min) ...       3.39 Ratio
PLAT230_ALERT_2_C Hirshfeld Test Diff for    O31    -   C31      =       5.96 su
PLAT230_ALERT_2_C Hirshfeld Test Diff for    N41    -   C43      =       6.89 su
PLAT432_ALERT_2_C Short Inter X...Y Contact  C43    ..  C45      =       3.15 Ang.

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

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

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Computing details

Data collection: Syntex P2₁ Diffractometer Control Software (Syntex, 1973; cell refinement: Syntex P2₁ Diffractometer Control Software; data reduction: XP21 (Pavelčík, 1987); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXS97.

isopropyl 2-methyl-4-(3-nitrophenyl)-5,7-dioxo-4,5,6,7-tetrahydro-1H- pyrrolo[3,4-b]pyridine-3-carboxylate

Crystal data

C18H17N3O6	Z = 2
Mr = 371.35	F(000) = 388
Triclinic, P1	Dx = 1.451 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71069 Å
a = 8.555 (3) Å	Cell parameters from 25 reflections
b = 9.445 (2) Å	θ = 6.8–19.3°
c = 11.322 (4) Å	µ = 0.11 mm^−1
α = 83.76 (2)°	T = 293 K
β = 72.52 (3)°	Prism, yellow
γ = 77.18 (2)°	0.4 × 0.3 × 0.3 mm
V = 850.0 (5) Å^3

Data collection

Syntex P21 diffractometer	Rint = 0.000
Radiation source: fine-focus sealed tube	θmax = 28.0°, θmin = 1.9°
Graphite monochromator	h = 0→11
θ/2θ scans	k = −12→12
4128 measured reflections	l = −13→14
4128 independent reflections	2 standard reflections every 100 min
1439 reflections with I > 2σ(I)	intensity decay: none

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.060	H-atom parameters constrained
wR(F^2) = 0.083	w = 1/[σ^2(Fo^2) + (0.0121P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.88	(Δ/σ)max = 0.001
4128 reflections	Δρmax = 0.18 e Å^−3
248 parameters	Δρmin = −0.20 e Å^−3
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0111 (6)

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O31	0.7852 (3)	0.47354 (19)	0.57144 (17)	0.0627 (7)
O32	0.8935 (2)	0.32963 (17)	0.70457 (16)	0.0436 (5)
O41	0.5892 (3)	0.1351 (2)	1.22031 (17)	0.0681 (7)
O42	0.8341 (3)	0.0584 (3)	1.1124 (2)	0.1105 (11)
O5	0.8806 (2)	−0.21698 (18)	0.73356 (16)	0.0460 (6)
O7	0.6814 (3)	−0.17335 (19)	0.39741 (17)	0.0561 (6)
N1	0.7148 (3)	0.1096 (2)	0.44099 (18)	0.0407 (7)
H1	0.6782	0.1093	0.3782	0.049*
N41	0.6905 (4)	0.1058 (3)	1.1217 (2)	0.0556 (8)
N6	0.7846 (3)	−0.2351 (2)	0.56719 (19)	0.0437 (7)
H6	0.7905	−0.3275	0.5721	0.052*
C2	0.7403 (3)	0.2307 (3)	0.4757 (2)	0.0373 (8)
C3	0.7937 (3)	0.2306 (2)	0.5751 (2)	0.0301 (7)
C4	0.8223 (3)	0.1022 (2)	0.6638 (2)	0.0300 (7)
H4	0.9367	0.0856	0.6702	0.036*
C5	0.8284 (4)	−0.1637 (3)	0.6489 (2)	0.0364 (8)
C7	0.7319 (4)	−0.1474 (3)	0.4795 (3)	0.0393 (8)
C9	0.8012 (3)	−0.0177 (3)	0.6060 (2)	0.0303 (7)
C8	0.7487 (3)	−0.0091 (3)	0.5077 (2)	0.0313 (7)
C22	0.7038 (4)	0.3505 (3)	0.3902 (2)	0.0530 (9)
H22A	0.7160	0.4388	0.4181	0.079*
H22B	0.5912	0.3601	0.3866	0.079*
H22C	0.7800	0.3319	0.3092	0.079*
C31	0.8209 (4)	0.3580 (3)	0.6132 (2)	0.0426 (8)
C32	0.9057 (4)	0.4451 (3)	0.7696 (3)	0.0524 (9)
H32	0.9341	0.5264	0.7113	0.063*
C33	0.7395 (4)	0.4918 (3)	0.8609 (3)	0.0810 (12)
H33A	0.6567	0.5274	0.8176	0.122*
H33B	0.7450	0.5677	0.9086	0.122*
H33C	0.7098	0.4106	0.9152	0.122*
C34	1.0421 (4)	0.3875 (3)	0.8290 (3)	0.0759 (11)
H34A	1.0141	0.3073	0.8854	0.114*
H34B	1.0554	0.4628	0.8735	0.114*
H34C	1.1448	0.3552	0.7663	0.114*
C41	0.6984 (4)	0.1246 (2)	0.7912 (2)	0.0290 (7)
C42	0.7518 (3)	0.1009 (2)	0.8964 (2)	0.0360 (7)
H42	0.8645	0.0677	0.8907	0.043*
C43	0.6365 (4)	0.1271 (3)	1.0091 (2)	0.0345 (7)
C44	0.4705 (4)	0.1738 (3)	1.0237 (2)	0.0411 (8)
H44	0.3956	0.1911	1.1018	0.049*
C45	0.4167 (4)	0.1946 (3)	0.9194 (2)	0.0433 (8)
H45	0.3034	0.2257	0.9264	0.052*
C46	0.5303 (4)	0.1696 (3)	0.8035 (2)	0.0385 (8)
H46	0.4924	0.1835	0.7335	0.046*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O31	0.110 (2)	0.0245 (11)	0.0714 (14)	−0.0181 (13)	−0.0536 (14)	0.0093 (10)
O32	0.0652 (16)	0.0240 (10)	0.0498 (12)	−0.0081 (10)	−0.0280 (12)	−0.0045 (9)
O41	0.089 (2)	0.0831 (16)	0.0288 (11)	−0.0126 (14)	−0.0127 (13)	−0.0100 (11)
O42	0.067 (2)	0.206 (3)	0.0508 (16)	0.013 (2)	−0.0326 (16)	−0.0150 (16)
O5	0.0680 (16)	0.0309 (11)	0.0389 (11)	−0.0026 (11)	−0.0214 (11)	0.0011 (9)
O7	0.0752 (17)	0.0457 (13)	0.0590 (13)	−0.0103 (11)	−0.0327 (13)	−0.0167 (10)
N1	0.0563 (19)	0.0375 (14)	0.0321 (13)	−0.0056 (13)	−0.0205 (13)	−0.0030 (11)
N41	0.066 (2)	0.0636 (19)	0.0379 (17)	−0.0117 (18)	−0.0163 (18)	−0.0034 (14)
N6	0.069 (2)	0.0224 (13)	0.0443 (15)	−0.0111 (13)	−0.0198 (14)	−0.0062 (11)
C2	0.046 (2)	0.0287 (16)	0.0343 (16)	−0.0067 (16)	−0.0084 (16)	0.0000 (13)
C3	0.041 (2)	0.0223 (15)	0.0283 (15)	−0.0078 (14)	−0.0114 (15)	0.0006 (12)
C4	0.0363 (19)	0.0259 (15)	0.0283 (14)	−0.0054 (14)	−0.0105 (14)	−0.0016 (12)
C5	0.046 (2)	0.0324 (17)	0.0289 (15)	−0.0071 (15)	−0.0078 (16)	−0.0035 (14)
C7	0.039 (2)	0.0374 (18)	0.0405 (18)	−0.0105 (16)	−0.0047 (17)	−0.0121 (15)
C9	0.041 (2)	0.0225 (15)	0.0265 (14)	−0.0085 (14)	−0.0063 (15)	−0.0017 (12)
C8	0.039 (2)	0.0263 (15)	0.0277 (15)	−0.0063 (15)	−0.0058 (15)	−0.0059 (12)
C22	0.072 (3)	0.0405 (18)	0.0452 (18)	−0.0059 (18)	−0.0228 (18)	0.0097 (14)
C31	0.051 (2)	0.0364 (19)	0.0411 (18)	−0.0094 (18)	−0.0133 (17)	−0.0038 (15)
C32	0.082 (3)	0.0252 (16)	0.058 (2)	−0.0132 (18)	−0.028 (2)	−0.0066 (15)
C33	0.107 (3)	0.049 (2)	0.080 (2)	−0.006 (2)	−0.014 (2)	−0.0283 (18)
C34	0.110 (3)	0.059 (2)	0.082 (2)	−0.016 (2)	−0.060 (2)	−0.0111 (18)
C41	0.038 (2)	0.0210 (14)	0.0299 (16)	−0.0067 (14)	−0.0112 (15)	−0.0020 (11)
C42	0.037 (2)	0.0353 (16)	0.0358 (17)	−0.0036 (14)	−0.0113 (16)	−0.0065 (13)
C43	0.042 (2)	0.0360 (16)	0.0298 (16)	−0.0075 (16)	−0.0172 (17)	−0.0029 (13)
C44	0.059 (3)	0.0306 (16)	0.0303 (17)	−0.0065 (17)	−0.0081 (17)	−0.0057 (13)
C45	0.040 (2)	0.0440 (19)	0.0446 (18)	−0.0017 (16)	−0.0131 (17)	−0.0052 (14)
C46	0.049 (2)	0.0398 (17)	0.0272 (16)	−0.0060 (16)	−0.0134 (16)	−0.0018 (13)

Geometric parameters (Å, º)

O31—C31	1.155 (3)	C9—C8	1.309 (3)
O32—C31	1.334 (3)	C22—H22A	0.9600
O32—C32	1.418 (3)	C22—H22B	0.9600
O41—N41	1.205 (3)	C22—H22C	0.9600
O42—N41	1.187 (3)	C32—C33	1.491 (4)
O5—C5	1.193 (3)	C32—C34	1.491 (4)
O7—C7	1.203 (3)	C32—H32	0.9800
N1—C8	1.309 (3)	C33—H33A	0.9600
N1—C2	1.331 (3)	C33—H33B	0.9600
N1—H1	0.8600	C33—H33C	0.9600
N41—C43	1.462 (3)	C34—H34A	0.9600
N6—C7	1.341 (3)	C34—H34B	0.9600
N6—C5	1.382 (3)	C34—H34C	0.9600
N6—H6	0.8600	C41—C46	1.374 (3)
C2—C3	1.335 (3)	C41—C42	1.379 (3)
C2—C22	1.450 (3)	C42—C43	1.366 (3)
C3—C31	1.409 (3)	C42—H42	0.9300
C3—C4	1.513 (3)	C43—C44	1.355 (3)
C4—C9	1.438 (3)	C44—C45	1.371 (3)
C4—C41	1.515 (3)	C44—H44	0.9300
C4—H4	0.9800	C45—C46	1.386 (3)
C5—C9	1.404 (3)	C45—H45	0.9300
C7—C8	1.425 (3)	C46—H46	0.9300
C31—O32—C32	120.1 (2)	O31—C31—O32	123.4 (3)
C8—N1—C2	116.4 (2)	O31—C31—C3	124.8 (3)
C8—N1—H1	121.8	O32—C31—C3	111.7 (2)
C2—N1—H1	121.8	O32—C32—C33	107.5 (3)
O42—N41—O41	122.2 (3)	O32—C32—C34	106.7 (2)
O42—N41—C43	118.1 (3)	C33—C32—C34	113.1 (3)
O41—N41—C43	119.6 (3)	O32—C32—H32	109.8
C7—N6—C5	114.0 (2)	C33—C32—H32	109.8
C7—N6—H6	123.0	C34—C32—H32	109.8
C5—N6—H6	123.0	C32—C33—H33A	109.5
N1—C2—C3	121.3 (2)	C32—C33—H33B	109.5
N1—C2—C22	109.6 (2)	H33A—C33—H33B	109.5
C3—C2—C22	129.0 (3)	C32—C33—H33C	109.5
C2—C3—C31	122.0 (2)	H33A—C33—H33C	109.5
C2—C3—C4	126.2 (2)	H33B—C33—H33C	109.5
C31—C3—C4	111.8 (2)	C32—C34—H34A	109.5
C9—C4—C3	103.8 (2)	C32—C34—H34B	109.5
C9—C4—C41	111.5 (2)	H34A—C34—H34B	109.5
C3—C4—C41	111.7 (2)	C32—C34—H34C	109.5
C9—C4—H4	109.9	H34A—C34—H34C	109.5
C3—C4—H4	109.9	H34B—C34—H34C	109.5
C41—C4—H4	109.9	C46—C41—C42	118.8 (3)
O5—C5—N6	127.0 (2)	C46—C41—C4	120.3 (2)
O5—C5—C9	129.4 (3)	C42—C41—C4	120.8 (3)
N6—C5—C9	103.6 (2)	C43—C42—C41	118.9 (3)
O7—C7—N6	130.9 (3)	C43—C42—H42	120.5
O7—C7—C8	127.1 (3)	C41—C42—H42	120.5
N6—C7—C8	102.0 (2)	C44—C43—C42	123.4 (3)
C8—C9—C5	108.7 (2)	C44—C43—N41	116.6 (3)
C8—C9—C4	126.0 (2)	C42—C43—N41	120.0 (3)
C5—C9—C4	125.2 (2)	C43—C44—C45	117.8 (3)
C9—C8—N1	125.8 (2)	C43—C44—H44	121.1
C9—C8—C7	111.6 (3)	C45—C44—H44	121.1
N1—C8—C7	122.6 (2)	C44—C45—C46	120.4 (3)
C2—C22—H22A	109.5	C44—C45—H45	119.8
C2—C22—H22B	109.5	C46—C45—H45	119.8
H22A—C22—H22B	109.5	C41—C46—C45	120.7 (3)
C2—C22—H22C	109.5	C41—C46—H46	119.7
H22A—C22—H22C	109.5	C45—C46—H46	119.7
H22B—C22—H22C	109.5
C8—N1—C2—C3	−1.5 (4)	N6—C7—C8—C9	−2.0 (3)
C8—N1—C2—C22	177.7 (3)	O7—C7—C8—N1	−2.7 (5)
N1—C2—C3—C31	−179.9 (3)	N6—C7—C8—N1	177.8 (3)
C22—C2—C3—C31	1.0 (5)	C32—O32—C31—O31	10.5 (5)
N1—C2—C3—C4	−3.7 (4)	C32—O32—C31—C3	−169.4 (2)
C22—C2—C3—C4	177.2 (3)	C2—C3—C31—O31	8.0 (5)
C2—C3—C4—C9	7.6 (4)	C4—C3—C31—O31	−168.7 (3)
C31—C3—C4—C9	−175.9 (2)	C2—C3—C31—O32	−172.2 (3)
C2—C3—C4—C41	−112.6 (3)	C4—C3—C31—O32	11.2 (3)
C31—C3—C4—C41	63.9 (3)	C31—O32—C32—C33	78.9 (3)
C7—N6—C5—O5	−179.0 (3)	C31—O32—C32—C34	−159.5 (2)
C7—N6—C5—C9	−0.6 (3)	C9—C4—C41—C46	−66.9 (3)
C5—N6—C7—O7	−177.9 (3)	C3—C4—C41—C46	48.7 (3)
C5—N6—C7—C8	1.5 (3)	C9—C4—C41—C42	113.4 (3)
O5—C5—C9—C8	177.6 (3)	C3—C4—C41—C42	−131.0 (2)
N6—C5—C9—C8	−0.7 (3)	C46—C41—C42—C43	−1.9 (4)
O5—C5—C9—C4	−4.4 (5)	C4—C41—C42—C43	177.8 (2)
N6—C5—C9—C4	177.2 (2)	C41—C42—C43—C44	0.9 (4)
C3—C4—C9—C8	−7.6 (4)	C41—C42—C43—N41	−178.7 (2)
C41—C4—C9—C8	112.8 (3)	O42—N41—C43—C44	176.4 (3)
C3—C4—C9—C5	174.8 (3)	O41—N41—C43—C44	−2.8 (4)
C41—C4—C9—C5	−64.8 (4)	O42—N41—C43—C42	−3.9 (4)
C5—C9—C8—N1	−178.1 (3)	O41—N41—C43—C42	176.8 (3)
C4—C9—C8—N1	4.0 (5)	C42—C43—C44—C45	0.4 (4)
C5—C9—C8—C7	1.7 (3)	N41—C43—C44—C45	180.0 (2)
C4—C9—C8—C7	−176.2 (3)	C43—C44—C45—C46	−0.6 (4)
C2—N1—C8—C9	1.6 (4)	C42—C41—C46—C45	1.7 (4)
C2—N1—C8—C7	−178.2 (3)	C4—C41—C46—C45	−178.0 (2)
O7—C7—C8—C9	177.4 (3)	C44—C45—C46—C41	−0.4 (4)