(S)-(–)-2,3-Dimeth­oxy-8-oxoberbine

In the title optically active protoberberine derivative [systematic name: (S)-(−)-2,3-dimeth­oxy-5,6,13,13a-tetra­hydro-8H-dibenzo[a,g]quinolizin-8-one], C₁₉H₁₉NO₃, the key inter­mediate in the synthesis of enanti­omerically pure (S)-(−)-O-methyl­bharatamine, the absolute configuration of the asymmetric centre at the 13a position has been confirmed as S by crystal structure refinement. The H atom at the asymmetric centre assumes an α-orientation and occupies a pseudo-axial position relative to the central non-planar rings of the tetra­cyclic skeleton.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.038
• wR factor = 0.093
• Data-to-parameter ratio = 13.5

checkCIF/PLATON results

No syntax errors found



Alert level C
RINTA01_ALERT_3_C  The value of Rint is greater than 0.10
            Rint given   0.121
PLAT020_ALERT_3_C The value of Rint is greater than 0.10 .........       0.12
PLAT199_ALERT_1_C Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_C Check the Reported _diffrn_ambient_temperature .        293 K

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           70.10
           From the CIF: _reflns_number_total               2849
           Count of symmetry unique reflns         1609
           Completeness (_total/calc)            177.07%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured      1240
           Fraction of Friedel pairs measured     0.771
           Are heavy atom types Z>Si present         no

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

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

---

Computing details

Data collection: KM-4 Software (Kuma Diffraction, 1996); cell refinement: KM-4 Software; data reduction: KM-4 Software; program(s) used to solve structure: SIR92 (Altomare et al., 1993); 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).

(S)-(-)-2,3-dimethoxy-5,6,13,13a-tetrahydro-8H-dibenzo[a,g]quinolizin-8-one

Crystal data

C19H19NO3	F(000) = 328
Mr = 309.35	Dx = 1.319 Mg m^−3
Monoclinic, P21	Melting point = 442–445 K
Hall symbol: P 2yb	Cu Kα radiation, λ = 1.54178 Å
a = 7.9530 (12) Å	Cell parameters from 53 reflections
b = 7.7145 (12) Å	θ = 12.8–30.1°
c = 12.7627 (12) Å	µ = 0.72 mm^−1
β = 95.76 (1)°	T = 293 K
V = 779.08 (18) Å^3	Block, colourless
Z = 2	0.52 × 0.16 × 0.12 mm

Data collection

Kuma Diffraction KM-4 diffractometer	Rint = 0.121
Radiation source: fine-focus sealed tube	θmax = 70.1°, θmin = 3.5°
Graphite monochromator	h = −9→9
ω–2θ scans	k = −9→9
2960 measured reflections	l = 0→15
2849 independent reflections	2 standard reflections every 100 reflections
2801 reflections with I > 2σ(I)	intensity decay: 2%

Refinement

Refinement on F^2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F^2 > 2σ(F^2)] = 0.038	w = 1/[σ^2(Fo^2) + (0.0621P)^2 + 0.0533P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.093	(Δ/σ)max < 0.001
S = 1.10	Δρmax = 0.16 e Å^−3
2849 reflections	Δρmin = −0.20 e Å^−3
211 parameters	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
1 restraint	Extinction coefficient: 0.081 (4)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), 1239 Friedel reflections
Secondary atom site location: difference Fourier map	Absolute structure parameter: 0.08 (18)

Special details

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.

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

	x	y	z	Uiso*/Ueq
O1	0.58907 (14)	0.41317 (19)	0.49932 (8)	0.0598 (3)
O2	0.85943 (12)	0.26302 (15)	0.58292 (7)	0.0487 (3)
O3	0.96905 (14)	0.2051 (2)	−0.07910 (9)	0.0729 (4)
C1	0.67425 (17)	0.3791 (2)	0.32315 (11)	0.0428 (3)
H1	0.5798	0.4395	0.2939	0.051*
C2	0.69749 (17)	0.35570 (19)	0.43050 (11)	0.0425 (3)
C3	0.84286 (16)	0.27113 (19)	0.47546 (10)	0.0405 (3)
C4	0.95434 (17)	0.20359 (19)	0.41050 (11)	0.0436 (3)
H4	1.0487	0.1433	0.4400	0.052*
C4a	0.92903 (16)	0.22357 (19)	0.30089 (10)	0.0417 (3)
C5	1.05367 (19)	0.1490 (2)	0.23227 (12)	0.0516 (4)
H51	1.0258	0.0287	0.2168	0.062*
H52	1.1662	0.1530	0.2693	0.062*
C6	1.05131 (17)	0.2494 (3)	0.13081 (11)	0.0539 (4)
H61	1.0955	0.3651	0.1453	0.065*
H62	1.1229	0.1923	0.0842	0.065*
N7	0.87863 (13)	0.26077 (18)	0.07963 (9)	0.0449 (3)
C8	0.85489 (18)	0.2480 (2)	−0.02678 (11)	0.0498 (4)
C8a	0.68217 (18)	0.2847 (2)	−0.07827 (11)	0.0456 (3)
C9	0.6568 (2)	0.2920 (3)	−0.18783 (12)	0.0573 (4)
H9	0.7475	0.2759	−0.2275	0.069*
C10	0.4986 (2)	0.3228 (3)	−0.23741 (12)	0.0613 (4)
H10	0.4825	0.3292	−0.3105	0.074*
C11	0.3636 (2)	0.3443 (2)	−0.17914 (12)	0.0585 (4)
H11	0.2560	0.3629	−0.2130	0.070*
C12	0.38750 (19)	0.3382 (2)	−0.07048 (12)	0.0513 (4)
H12	0.2959	0.3533	−0.0315	0.062*
C12a	0.54657 (17)	0.3097 (2)	−0.01930 (10)	0.0422 (3)
C13	0.57665 (16)	0.3011 (2)	0.09822 (10)	0.0453 (3)
H131	0.5543	0.1841	0.1210	0.054*
H132	0.4980	0.3780	0.1284	0.054*
C13a	0.75612 (16)	0.35121 (18)	0.13974 (10)	0.0407 (3)
H13a	0.7690	0.4761	0.1292	0.049*
C13b	0.78929 (16)	0.31416 (18)	0.25701 (10)	0.0392 (3)
C14	0.4237 (2)	0.4535 (4)	0.45820 (14)	0.0778 (7)
H141	0.4256	0.5515	0.4119	0.117*
H142	0.3574	0.4809	0.5148	0.117*
H143	0.3749	0.3559	0.4197	0.117*
C15	1.0089 (2)	0.1862 (3)	0.63134 (11)	0.0585 (4)
H151	1.0156	0.0682	0.6083	0.088*
H152	1.0075	0.1890	0.7064	0.088*
H153	1.1052	0.2494	0.6121	0.088*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0560 (6)	0.0869 (9)	0.0380 (5)	0.0238 (6)	0.0121 (4)	−0.0017 (5)
O2	0.0468 (5)	0.0645 (7)	0.0344 (5)	0.0074 (5)	0.0024 (4)	0.0034 (4)
O3	0.0531 (6)	0.1200 (12)	0.0485 (6)	0.0090 (7)	0.0201 (5)	−0.0161 (7)
C1	0.0424 (6)	0.0496 (7)	0.0365 (6)	0.0094 (6)	0.0051 (5)	0.0001 (6)
C2	0.0423 (7)	0.0487 (7)	0.0374 (6)	0.0057 (6)	0.0088 (5)	−0.0011 (5)
C3	0.0426 (6)	0.0445 (7)	0.0343 (6)	−0.0005 (6)	0.0035 (5)	0.0025 (5)
C4	0.0383 (6)	0.0504 (8)	0.0420 (7)	0.0056 (6)	0.0033 (5)	0.0027 (6)
C4a	0.0391 (6)	0.0465 (7)	0.0400 (6)	0.0029 (6)	0.0066 (5)	−0.0004 (6)
C5	0.0421 (7)	0.0647 (9)	0.0492 (8)	0.0126 (7)	0.0098 (6)	−0.0010 (7)
C6	0.0383 (7)	0.0769 (11)	0.0480 (7)	−0.0008 (8)	0.0119 (5)	−0.0002 (8)
N7	0.0383 (5)	0.0593 (8)	0.0387 (6)	0.0008 (5)	0.0113 (4)	−0.0031 (5)
C8	0.0488 (7)	0.0620 (9)	0.0405 (7)	−0.0028 (7)	0.0138 (6)	−0.0055 (7)
C8a	0.0502 (7)	0.0506 (8)	0.0369 (6)	−0.0072 (6)	0.0094 (5)	−0.0047 (6)
C9	0.0622 (9)	0.0731 (11)	0.0385 (7)	−0.0100 (8)	0.0136 (6)	−0.0090 (7)
C10	0.0748 (10)	0.0741 (11)	0.0339 (7)	−0.0091 (9)	−0.0001 (6)	−0.0069 (7)
C11	0.0580 (8)	0.0704 (11)	0.0448 (8)	−0.0053 (8)	−0.0069 (6)	−0.0037 (7)
C12	0.0483 (7)	0.0624 (9)	0.0432 (7)	−0.0026 (7)	0.0045 (6)	−0.0013 (7)
C12a	0.0458 (7)	0.0458 (7)	0.0353 (6)	−0.0029 (6)	0.0062 (5)	−0.0014 (5)
C13	0.0402 (6)	0.0628 (9)	0.0341 (6)	0.0036 (6)	0.0100 (5)	0.0015 (6)
C13a	0.0435 (7)	0.0449 (7)	0.0349 (6)	0.0025 (6)	0.0102 (5)	−0.0014 (5)
C13b	0.0395 (6)	0.0425 (7)	0.0360 (6)	0.0019 (5)	0.0058 (5)	−0.0009 (5)
C14	0.0602 (10)	0.1221 (19)	0.0538 (9)	0.0431 (11)	0.0179 (7)	0.0093 (11)
C15	0.0565 (8)	0.0779 (11)	0.0394 (7)	0.0154 (8)	−0.0038 (6)	0.0007 (7)

Geometric parameters (Å, º)

O1—C2	1.3651 (16)	C8a—C12a	1.3892 (18)
O1—C14	1.4011 (19)	C8a—C9	1.3937 (19)
O2—C3	1.3660 (15)	C9—C10	1.372 (2)
O2—C15	1.4139 (18)	C9—H9	0.9300
O3—C8	1.2254 (17)	C10—C11	1.376 (2)
C1—C2	1.3759 (18)	C10—H10	0.9300
C1—C13b	1.3984 (17)	C11—C12	1.381 (2)
C1—H1	0.9300	C11—H11	0.9300
C2—C3	1.3994 (19)	C12—C12a	1.382 (2)
C3—C4	1.3756 (18)	C12—H12	0.9300
C4—C4a	1.4017 (18)	C12a—C13	1.4965 (17)
C4—H4	0.9300	C13—C13a	1.5218 (19)
C4a—C13b	1.3828 (18)	C13—H131	0.9700
C4a—C5	1.5015 (19)	C13—H132	0.9700
C5—C6	1.507 (2)	C13a—C13b	1.5206 (17)
C5—H51	0.9700	C13a—H13a	0.9800
C5—H52	0.9700	C14—H141	0.9600
C6—N7	1.4630 (18)	C14—H142	0.9600
C6—H61	0.9700	C14—H143	0.9600
C6—H62	0.9700	C15—H151	0.9600
N7—C8	1.3558 (17)	C15—H152	0.9600
N7—C13a	1.4747 (16)	C15—H153	0.9600
C8—C8a	1.489 (2)
C2—O1—C14	117.45 (12)	C8a—C9—H9	119.9
C3—O2—C15	116.75 (10)	C9—C10—C11	120.07 (14)
C2—C1—C13b	121.56 (12)	C9—C10—H10	120.0
C2—C1—H1	119.2	C11—C10—H10	120.0
C13b—C1—H1	119.2	C10—C11—C12	120.14 (15)
O1—C2—C1	124.59 (12)	C10—C11—H11	119.9
O1—C2—C3	115.90 (12)	C12—C11—H11	119.9
C1—C2—C3	119.50 (12)	C11—C12—C12a	120.48 (13)
O2—C3—C4	125.78 (11)	C11—C12—H12	119.8
O2—C3—C2	115.18 (11)	C12a—C12—H12	119.8
C4—C3—C2	119.04 (11)	C12—C12a—C8a	119.32 (12)
C3—C4—C4a	121.54 (12)	C12—C12a—C13	121.84 (11)
C3—C4—H4	119.2	C8a—C12a—C13	118.82 (12)
C4a—C4—H4	119.2	C12a—C13—C13a	112.81 (11)
C13b—C4a—C4	119.27 (12)	C12a—C13—H131	109.0
C13b—C4a—C5	120.54 (12)	C13a—C13—H131	109.0
C4—C4a—C5	120.19 (12)	C12a—C13—H132	109.0
C4a—C5—C6	110.62 (13)	C13a—C13—H132	109.0
C4a—C5—H51	109.5	H131—C13—H132	107.8
C6—C5—H51	109.5	N7—C13a—C13b	111.39 (11)
C4a—C5—H52	109.5	N7—C13a—C13	110.13 (11)
C6—C5—H52	109.5	C13b—C13a—C13	111.04 (10)
H51—C5—H52	108.1	N7—C13a—H13a	108.1
N7—C6—C5	110.15 (12)	C13b—C13a—H13a	108.1
N7—C6—H61	109.6	C13—C13a—H13a	108.1
C5—C6—H61	109.6	C4a—C13b—C1	118.98 (11)
N7—C6—H62	109.6	C4a—C13b—C13a	123.14 (11)
C5—C6—H62	109.6	C1—C13b—C13a	117.86 (11)
H61—C6—H62	108.1	O1—C14—H141	109.5
C8—N7—C6	118.23 (10)	O1—C14—H142	109.5
C8—N7—C13a	121.50 (11)	H141—C14—H142	109.5
C6—N7—C13a	115.83 (11)	O1—C14—H143	109.5
O3—C8—N7	121.95 (13)	H141—C14—H143	109.5
O3—C8—C8a	120.79 (12)	H142—C14—H143	109.5
N7—C8—C8a	117.25 (11)	O2—C15—H151	109.5
C12a—C8a—C9	119.73 (13)	O2—C15—H152	109.5
C12a—C8a—C8	121.28 (12)	H151—C15—H152	109.5
C9—C8a—C8	118.99 (12)	O2—C15—H153	109.5
C10—C9—C8a	120.23 (14)	H151—C15—H153	109.5
C10—C9—H9	119.9	H152—C15—H153	109.5
C14—O1—C2—C1	19.0 (3)	C8—C8a—C9—C10	178.97 (18)
C14—O1—C2—C3	−162.55 (17)	C8a—C9—C10—C11	−0.9 (3)
C13b—C1—C2—O1	−178.93 (14)	C9—C10—C11—C12	1.2 (3)
C13b—C1—C2—C3	2.6 (2)	C10—C11—C12—C12a	−0.3 (3)
C15—O2—C3—C4	3.5 (2)	C11—C12—C12a—C8a	−1.0 (2)
C15—O2—C3—C2	−176.91 (15)	C11—C12—C12a—C13	−179.54 (16)
O1—C2—C3—O2	−2.23 (19)	C9—C8a—C12a—C12	1.3 (2)
C1—C2—C3—O2	176.35 (13)	C8—C8a—C12a—C12	−178.03 (15)
O1—C2—C3—C4	177.39 (13)	C9—C8a—C12a—C13	179.91 (15)
C1—C2—C3—C4	−4.0 (2)	C8—C8a—C12a—C13	0.6 (2)
O2—C3—C4—C4a	−177.86 (13)	C12—C12a—C13—C13a	−153.69 (15)
C2—C3—C4—C4a	2.6 (2)	C8a—C12a—C13—C13a	27.7 (2)
C3—C4—C4a—C13b	0.4 (2)	C8—N7—C13a—C13b	167.37 (13)
C3—C4—C4a—C5	179.67 (14)	C6—N7—C13a—C13b	−36.70 (16)
C13b—C4a—C5—C6	25.6 (2)	C8—N7—C13a—C13	43.72 (17)
C4—C4a—C5—C6	−153.65 (14)	C6—N7—C13a—C13	−160.36 (13)
C4a—C5—C6—N7	−52.99 (19)	C12a—C13—C13a—N7	−47.37 (17)
C5—C6—N7—C8	−141.65 (15)	C12a—C13—C13a—C13b	−171.23 (12)
C5—C6—N7—C13a	61.60 (19)	C4—C4a—C13b—C1	−1.9 (2)
C6—N7—C8—O3	9.7 (2)	C5—C4a—C13b—C1	178.87 (14)
C13a—N7—C8—O3	165.11 (17)	C4—C4a—C13b—C13a	176.52 (13)
C6—N7—C8—C8a	−171.58 (15)	C5—C4a—C13b—C13a	−2.8 (2)
C13a—N7—C8—C8a	−16.2 (2)	C2—C1—C13b—C4a	0.4 (2)
O3—C8—C8a—C12a	170.95 (18)	C2—C1—C13b—C13a	−178.11 (13)
N7—C8—C8a—C12a	−7.8 (2)	N7—C13a—C13b—C4a	7.01 (18)
O3—C8—C8a—C9	−8.4 (2)	C13—C13a—C13b—C4a	130.15 (14)
N7—C8—C8a—C9	172.90 (16)	N7—C13a—C13b—C1	−174.60 (12)
C12a—C8a—C9—C10	−0.4 (3)	C13—C13a—C13b—C1	−51.46 (17)