Anisotropic crystal structure distortion of the monoclinic polymorph of acetaminophen at high hydrostatic pressures

The anisotropy of structural distortion of the monoclinic polymorph of acetaminophen induced by hydrostatic pressure up to 4.0 GPa was studied by single-crystal X-ray diffraction in a Merrill–Bassett diamond anvil cell (DAC). The space group (P2₁/n) and the general structural pattern remained unchanged with pressure. Despite the overall decrease in the molar volume with pressure, the structure expanded in particular crystallographic directions. One of the linear cell parameters (c) passed through a minimum as the pressure increased. The intramolecular bond lengths changed only slightly with pressure, but the changes in the dihedral and torsion angles were very large. The compressibility of the intermolecular hydrogen bonds NH...O and OH...O was measured. NH...O bonds were shown to be slightly more compressible than OH...O bonds. The anisotropy of structural distortion was analysed in detail in relation to the pressure-induced changes in the molecular conformations, to the compression of the hydrogen-bond network, and to the changes in the orientation of molecules with respect to each other in the pleated sheets in the structure. Dirichlet domains were calculated in order to analyse the relative shifts of the centroids of the hydrogen-bonded cycles and of the centroids of the benzene rings with pressure.

Computing details

For all compounds, data collection: MDIF4 (Kutoglu, 1997); cell refinement: CRYMIS (Kutoglu, 1995); data reduction: PROFILE (Naumov and Boldyreva, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997b); molecular graphics: CAVITY (Naumov and Boldyreva, 1999); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997b).

(1.0GPa) 4-acetaminophenol

Crystal data

C8H9NO2	F(000) = 320
Mr = 151.16	Dx = 1.411 Mg m^−3
Monoclinic, P21/n	Melting point = 171–172 K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 6.980 (1) Å	Cell parameters from 12 reflections
b = 8.915 (2) Å	θ = 2.8–8.7°
c = 11.566 (2) Å	µ = 0.10 mm^−1
β = 98.54 (3)°	T = 293 K
V = 711.7 (2) Å^3	Prism, colourless
Z = 4	0.25 × 0.15 × 0.07 mm

Data collection

STOE 4-circle diffractometer	Rint = 0.049
Radiation source: fine-focus sealed tube	θmax = 27.5°, θmin = 2.9°
Graphite monochromator	h = −5→5
ω scans	k = −11→11
2585 measured reflections	l = −14→14
627 independent reflections	1 standard reflections every 300 min
328 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)] = 0.035	Combination
wR(F^2) = 0.053	w = 1/[σ^2(Fo^2) + (0.0189P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.84	(Δ/σ)max < 0.001
627 reflections	Δρmax = 0.10 e Å^−3
113 parameters	Δρmin = −0.07 e Å^−3
1 restraint	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.014 (3)

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	0.1594 (6)	0.9332 (2)	0.2213 (3)	0.050 (3)
H1'	0.071 (5)	0.981 (5)	0.240 (3)	0.060*
C1	0.1298 (8)	0.8364 (3)	0.1280 (3)	0.029 (3)
C2	−0.0470 (7)	0.8305 (2)	0.0547 (3)	0.038 (4)
H2	−0.161 (4)	0.896 (2)	0.0704 (5)	0.046*
C3	−0.0652 (8)	0.7338 (3)	−0.0400 (3)	0.031 (3)
H3	−0.181 (3)	0.7307 (3)	−0.0907 (12)	0.038*
C4	0.0824 (7)	0.6436 (3)	−0.0606 (3)	0.023 (4)
C5	0.2575 (6)	0.6468 (3)	0.0148 (2)	0.025 (3)
H5	0.356 (3)	0.586 (2)	0.0026 (5)	0.030*
C6	0.2784 (8)	0.7444 (3)	0.1088 (3)	0.032 (3)
H6	0.398 (3)	0.7474 (3)	0.1607 (12)	0.039*
N1	0.0475 (9)	0.5488 (3)	−0.1608 (3)	0.032 (4)
H2'	−0.080 (5)	0.5317 (6)	−0.1893 (10)	0.039*
C7	0.1765 (12)	0.4814 (4)	−0.2188 (4)	0.024 (4)
O2	0.3515 (7)	0.4873 (2)	−0.1883 (3)	0.047 (3)
C8	0.0868 (9)	0.3948 (3)	−0.3257 (3)	0.057 (4)
H8A	−0.045 (2)	0.419 (3)	−0.3430 (14)	0.085*
H8B	0.101 (4)	0.2917 (17)	−0.3110 (11)	0.085*
H8C	0.149 (2)	0.420 (2)	−0.3893 (13)	0.085*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.051 (6)	0.0438 (14)	0.050 (2)	0.0029 (16)	−0.011 (4)	−0.0182 (13)
C1	0.026 (8)	0.0294 (16)	0.031 (3)	0.001 (2)	0.006 (4)	0.0013 (15)
C2	0.032 (8)	0.0347 (16)	0.044 (3)	0.0117 (19)	−0.006 (5)	−0.0017 (15)
C3	0.026 (8)	0.0375 (17)	0.030 (3)	0.008 (2)	−0.001 (4)	−0.0029 (17)
C4	0.018 (8)	0.0265 (15)	0.026 (3)	−0.002 (2)	0.006 (5)	0.0056 (15)
C5	0.012 (8)	0.0331 (17)	0.032 (3)	0.0076 (17)	0.010 (5)	0.0048 (14)
C6	0.024 (8)	0.0372 (19)	0.033 (3)	0.000 (2)	−0.004 (5)	0.0022 (16)
N1	0.028 (8)	0.0338 (17)	0.032 (3)	0.002 (2)	−0.003 (5)	−0.0014 (13)
C7	0.011 (11)	0.031 (2)	0.034 (4)	0.005 (3)	0.015 (6)	0.0048 (18)
O2	0.028 (8)	0.0685 (17)	0.045 (3)	0.005 (2)	0.006 (4)	−0.0022 (13)
C8	0.082 (9)	0.0418 (17)	0.043 (3)	0.004 (2)	−0.002 (5)	−0.0113 (16)

Geometric parameters (Å, º)

O1—C1	1.373 (3)	C6—C1	1.366 (6)
C1—C2	1.391 (4)	C4—N1	1.426 (4)
C2—C3	1.385 (4)	N1—C7	1.342 (10)
C3—C4	1.356 (6)	C7—O2	1.221 (8)
C4—C5	1.392 (4)	C7—C8	1.511 (4)
C5—C6	1.383 (4)
O1—C1—C2	121.3 (4)	C5—C6—C1	120.8 (3)
C1—C2—C3	118.4 (4)	C6—C1—O1	118.4 (3)
C2—C3—C4	121.7 (3)	C6—C1—C2	120.3 (3)
C3—C4—C5	119.8 (3)	C4—N1—C7	128.7 (6)
C3—C4—N1	116.8 (3)	N1—C7—O2	123.6 (4)
C5—C4—N1	123.3 (4)	N1—C7—C8	114.2 (6)
C4—C5—C6	119.1 (4)	O2—C7—C8	122.2 (7)

(2.0GPa) 4-acetaminophenol

Crystal data

C8H9NO2	F(000) = 320
Mr = 151.16	Dx = 1.494 Mg m^−3
Monoclinic, P21/n	Melting point = 171–172 K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 6.885 (1) Å	Cell parameters from 12 reflections
b = 8.5819 (7) Å	θ = 3.0–9.0°
c = 11.519 (1) Å	µ = 0.11 mm^−1
β = 99.12 (1)°	T = 293 K
V = 672.01 (13) Å^3	Prism, colourless
Z = 4	0.25 × 0.15 × 0.07 mm

Data collection

STOE 4-circle diffractometer	Rint = 0.067
Radiation source: fine-focus sealed tube	θmax = 27.5°, θmin = 3.0°
Graphite monochromator	h = −5→5
ω scans	k = −11→11
2167 measured reflections	l = −13→13
613 independent reflections	1 standard reflections every 300 min
360 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)] = 0.033	Combination
wR(F^2) = 0.055	w = 1/[σ^2(Fo^2) + (0.P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.92	(Δ/σ)max < 0.001
613 reflections	Δρmax = 0.11 e Å^−3
113 parameters	Δρmin = −0.10 e Å^−3
2 restraints	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0080 (15)

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	0.1537 (5)	0.9479 (2)	0.2216 (2)	0.039 (2)
H1'	0.053 (4)	0.985 (4)	0.246 (3)	0.047*
C1	0.1228 (7)	0.8456 (3)	0.1292 (3)	0.022 (3)
C2	−0.0579 (6)	0.8346 (2)	0.0565 (2)	0.025 (3)
H2	−0.172 (4)	0.897 (2)	0.0719 (5)	0.030*
C3	−0.0748 (7)	0.7335 (3)	−0.0381 (3)	0.036 (3)
H3	−0.194 (3)	0.7270 (3)	−0.0883 (12)	0.044*
C4	0.0769 (6)	0.6436 (2)	−0.0601 (2)	0.015 (3)
C5	0.2589 (6)	0.6505 (2)	0.0146 (2)	0.028 (3)
H5	0.366 (3)	0.587 (2)	0.0011 (5)	0.033*
C6	0.2771 (7)	0.7527 (3)	0.1090 (3)	0.019 (3)
H6	0.397 (3)	0.7587 (3)	0.1601 (10)	0.023*
N1	0.0458 (7)	0.5454 (2)	−0.1610 (2)	0.020 (3)
H2'	−0.078 (4)	0.5306 (5)	−0.1909 (9)	0.024*
C7	0.1732 (9)	0.4727 (3)	−0.2172 (3)	0.031 (3)
O2	0.3530 (6)	0.4752 (2)	−0.1850 (2)	0.037 (3)
C8	0.0824 (7)	0.3854 (3)	−0.3257 (3)	0.041 (3)
H8A	0.153 (2)	0.409 (2)	−0.3889 (11)	0.061*
H8B	−0.052 (2)	0.416 (2)	−0.3472 (12)	0.061*
H8C	0.089 (4)	0.2756 (16)	−0.3101 (8)	0.061*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.035 (5)	0.0370 (12)	0.0412 (17)	0.0024 (13)	−0.006 (3)	−0.0150 (11)
C1	0.019 (6)	0.0262 (15)	0.022 (2)	−0.0019 (18)	0.007 (4)	0.0006 (13)
C2	0.016 (6)	0.0283 (14)	0.032 (2)	0.0082 (16)	0.006 (4)	−0.0003 (13)
C3	0.042 (7)	0.0280 (15)	0.032 (2)	0.0064 (18)	−0.015 (4)	0.0021 (14)
C4	0.013 (6)	0.0206 (13)	0.016 (2)	−0.0026 (18)	0.011 (4)	0.0034 (12)
C5	0.027 (6)	0.0258 (14)	0.028 (2)	0.0025 (16)	−0.002 (4)	0.0047 (13)
C6	0.003 (6)	0.0299 (16)	0.024 (2)	0.0022 (17)	0.003 (4)	0.0005 (14)
N1	0.009 (6)	0.0298 (14)	0.022 (2)	−0.0010 (17)	0.004 (3)	0.0016 (12)
C7	0.029 (8)	0.0215 (17)	0.039 (3)	0.005 (2)	0.000 (4)	0.0003 (16)
O2	0.016 (6)	0.0530 (14)	0.043 (2)	0.0040 (15)	0.007 (3)	−0.0003 (11)
C8	0.057 (7)	0.0314 (13)	0.033 (2)	0.0009 (19)	0.004 (4)	−0.0047 (13)

Geometric parameters (Å, º)

O1—C1	1.370 (3)	C6—C1	1.377 (6)
C1—C2	1.389 (4)	C4—N1	1.423 (3)
C2—C3	1.383 (4)	N1—C7	1.327 (8)
C3—C4	1.354 (6)	C7—O2	1.235 (6)
C4—C5	1.405 (4)	C7—C8	1.505 (3)
C5—C6	1.387 (4)
O1—C1—C2	121.7 (4)	C5—C6—C1	121.5 (3)
C1—C2—C3	118.2 (4)	C6—C1—O1	118.3 (3)
C2—C3—C4	122.3 (3)	C6—C1—C2	120.0 (3)
C3—C4—C5	120.1 (3)	C4—N1—C7	130.7 (4)
C3—C4—N1	118.0 (3)	N1—C7—O2	123.6 (3)
C5—C4—N1	121.9 (4)	N1—C7—C8	114.8 (5)
C4—C5—C6	117.9 (4)	O2—C7—C8	121.5 (5)

(3.0GPa) 4-acetaminophenol

Crystal data

C8H9NO2	F(000) = 320
Mr = 151.16	Dx = 1.541 Mg m^−3
Monoclinic, P21/n	Melting point = 171–172 K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 6.820 (1) Å	Cell parameters from 15 reflections
b = 8.374 (1) Å	θ = 3.0–9.1°
c = 11.559 (1) Å	µ = 0.11 mm^−1
β = 99.32 (1)°	T = 293 K
V = 651.43 (14) Å^3	Prism, colourless
Z = 4	0.25 × 0.15 × 0.07 mm

Data collection

STOE 4-circle diffractometer	Rint = 0.051
Radiation source: fine-focus sealed tube	θmax = 27.5°, θmin = 3.0°
Graphite monochromator	h = −5→5
ω scans	k = −10→10
2084 measured reflections	l = −13→13
601 independent reflections	1 standard reflections every 300 min
364 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)] = 0.031	Combination
wR(F^2) = 0.048	w = 1/[σ^2(Fo^2) + (0.P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.80	(Δ/σ)max < 0.001
601 reflections	Δρmax = 0.10 e Å^−3
113 parameters	Δρmin = −0.10 e Å^−3
1 restraint	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0119 (13)

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	0.1501 (5)	0.95610 (18)	0.2223 (2)	0.037 (2)
H1'	0.051 (4)	1.001 (4)	0.240 (3)	0.044*
C1	0.1206 (6)	0.8513 (2)	0.1294 (2)	0.027 (3)
C2	−0.0636 (6)	0.8375 (2)	0.0586 (2)	0.025 (3)
H2	−0.177 (4)	0.8982 (19)	0.0751 (6)	0.030*
C3	−0.0803 (7)	0.7346 (2)	−0.0364 (3)	0.032 (3)
H3	−0.202 (3)	0.7265 (3)	−0.0863 (11)	0.038*
C4	0.0747 (6)	0.6455 (2)	−0.0587 (2)	0.017 (3)
C5	0.2591 (5)	0.6553 (2)	0.0144 (2)	0.025 (3)
H5	0.369 (3)	0.5923 (19)	−0.0001 (5)	0.030*
C6	0.2775 (6)	0.7597 (3)	0.1089 (3)	0.019 (2)
H6	0.402 (3)	0.7677 (3)	0.1606 (10)	0.023*
N1	0.0415 (6)	0.5455 (2)	−0.1594 (2)	0.021 (2)
H2'	−0.091 (4)	0.5305 (4)	−0.1916 (9)	0.025*
C7	0.1716 (8)	0.4700 (3)	−0.2146 (3)	0.029 (3)
O2	0.3522 (5)	0.4694 (2)	−0.1808 (2)	0.032 (2)
C8	0.0795 (7)	0.3814 (3)	−0.3234 (2)	0.045 (3)
H8A	0.088 (4)	0.2680 (16)	−0.3087 (8)	0.068*
H8B	0.150 (2)	0.407 (2)	−0.3870 (11)	0.068*
H8C	−0.058 (2)	0.412 (2)	−0.3441 (11)	0.068*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.034 (5)	0.0349 (11)	0.0380 (16)	0.0041 (13)	−0.004 (3)	−0.0149 (10)
C1	0.034 (6)	0.0214 (14)	0.024 (2)	0.0003 (16)	−0.003 (3)	0.0022 (13)
C2	0.017 (6)	0.0267 (13)	0.031 (2)	0.0053 (15)	0.006 (4)	−0.0012 (12)
C3	0.035 (6)	0.0262 (14)	0.029 (2)	0.0065 (17)	−0.010 (3)	0.0026 (13)
C4	0.019 (6)	0.0189 (12)	0.015 (2)	−0.0049 (16)	0.006 (3)	0.0058 (11)
C5	0.025 (6)	0.0229 (14)	0.025 (2)	0.0009 (14)	0.001 (4)	0.0058 (12)
C6	0.007 (6)	0.0264 (13)	0.024 (2)	−0.0011 (16)	0.004 (3)	0.0056 (13)
N1	0.012 (5)	0.0281 (13)	0.0219 (19)	0.0014 (16)	0.003 (3)	0.0000 (11)
C7	0.031 (7)	0.0214 (15)	0.033 (3)	0.002 (2)	−0.002 (4)	0.0046 (14)
O2	0.013 (5)	0.0493 (12)	0.0351 (17)	0.0036 (13)	0.011 (3)	0.0010 (10)
C8	0.071 (6)	0.0264 (12)	0.034 (2)	0.0038 (18)	−0.005 (4)	−0.0036 (12)

Geometric parameters (Å, º)

O1—C1	1.377 (3)	C6—C1	1.368 (6)
C1—C2	1.388 (4)	C4—N1	1.422 (3)
C2—C3	1.385 (3)	N1—C7	1.333 (7)
C3—C4	1.353 (6)	C7—O2	1.231 (6)
C4—C5	1.400 (4)	C7—C8	1.507 (3)
C5—C6	1.389 (4)
O1—C1—C2	121.2 (4)	C5—C6—C1	121.0 (3)
C1—C2—C3	118.0 (4)	C6—C1—O1	118.2 (3)
C2—C3—C4	121.8 (3)	C6—C1—C2	120.6 (3)
C3—C4—C5	120.4 (2)	C4—N1—C7	129.9 (4)
C3—C4—N1	117.1 (3)	N1—C7—O2	124.0 (3)
C5—C4—N1	122.5 (4)	N1—C7—C8	114.4 (4)
C4—C5—C6	118.1 (4)	O2—C7—C8	121.6 (5)

(4.0GPa) 4-acetaminophenol

Crystal data

C8H9NO2	F(000) = 320
Mr = 151.16	Dx = 1.615 Mg m^−3
Monoclinic, P21/n	Melting point = 171–172 K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 6.625 (1) Å	Cell parameters from 15 reflections
b = 7.985 (2) Å	θ = 3.1–9.4°
c = 11.916 (2) Å	µ = 0.12 mm^−1
β = 99.41 (3)°	T = 293 K
V = 621.9 (2) Å^3	Prism, colourless
Z = 4	0.25 × 0.15 × 0.07 mm

Data collection

STOE 4-circle diffractometer	Rint = 0.047
Radiation source: fine-focus sealed tube	θmax = 27.5°, θmin = 3.1°
Graphite monochromator	h = −5→5
ω scans	k = −10→10
2008 measured reflections	l = −14→14
581 independent reflections	1 standard reflections every 300 min
351 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)] = 0.031	Combination
wR(F^2) = 0.063	w = 1/[σ^2(Fo^2) + (0.0185P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.89	(Δ/σ)max < 0.001
581 reflections	Δρmax = 0.12 e Å^−3
113 parameters	Δρmin = −0.11 e Å^−3
1 restraint	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.012 (2)

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	0.1447 (5)	0.9750 (2)	0.2205 (2)	0.033 (3)
H1'	0.042 (5)	1.013 (4)	0.243 (3)	0.040*
C1	0.1148 (8)	0.8669 (3)	0.1292 (3)	0.020 (3)
C2	−0.0785 (7)	0.8444 (3)	0.0648 (2)	0.018 (3)
H2	−0.190 (4)	0.898 (2)	0.0833 (7)	0.021*
C3	−0.0967 (8)	0.7377 (3)	−0.0281 (3)	0.027 (3)
H3	−0.228 (4)	0.7217 (5)	−0.0740 (12)	0.032*
C4	0.0684 (8)	0.6554 (3)	−0.0552 (3)	0.016 (3)
C5	0.2612 (6)	0.6722 (2)	0.0124 (2)	0.019 (3)
H5	0.375 (4)	0.614 (2)	−0.0047 (7)	0.023*
C6	0.2776 (7)	0.7783 (3)	0.1057 (3)	0.021 (3)
H6	0.405 (4)	0.7891 (4)	0.1541 (13)	0.026*
N1	0.0344 (7)	0.5533 (3)	−0.1546 (2)	0.024 (3)
H2'	−0.125 (6)	0.543 (3)	−0.179 (3)	0.029*
C7	0.1673 (9)	0.4686 (3)	−0.2041 (3)	0.027 (4)
O2	0.3534 (6)	0.4672 (2)	−0.1692 (2)	0.031 (2)
C8	0.0812 (8)	0.3730 (3)	−0.3091 (3)	0.035 (3)
H8A	0.134 (3)	0.417 (2)	−0.3720 (12)	0.053*
H8B	−0.063 (2)	0.383 (2)	−0.3223 (10)	0.053*
H8C	0.118 (4)	0.259 (2)	−0.2993 (9)	0.053*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.034 (6)	0.0294 (13)	0.0327 (18)	0.0023 (16)	−0.004 (3)	−0.0113 (10)
C1	0.023 (7)	0.0187 (14)	0.019 (2)	−0.0009 (19)	0.006 (4)	0.0026 (13)
C2	0.010 (7)	0.0219 (13)	0.025 (2)	0.0068 (16)	0.012 (4)	0.0021 (13)
C3	0.032 (7)	0.0216 (14)	0.023 (2)	0.000 (2)	−0.007 (4)	0.0050 (14)
C4	0.016 (7)	0.0180 (13)	0.016 (2)	0.0010 (19)	0.006 (4)	0.0016 (13)
C5	0.018 (7)	0.0222 (13)	0.018 (2)	0.0012 (17)	0.008 (4)	0.0030 (12)
C6	0.021 (7)	0.0213 (14)	0.021 (2)	0.0012 (18)	0.000 (4)	0.0030 (13)
N1	0.023 (6)	0.0242 (13)	0.022 (2)	0.0002 (17)	−0.005 (4)	0.0015 (11)
C7	0.035 (8)	0.0175 (15)	0.027 (3)	0.002 (2)	−0.002 (5)	0.0072 (14)
O2	0.024 (6)	0.0369 (12)	0.0311 (18)	0.0037 (14)	0.003 (3)	0.0018 (10)
C8	0.054 (8)	0.0231 (14)	0.027 (2)	0.0017 (18)	−0.001 (4)	−0.0027 (12)

Geometric parameters (Å, º)

O1—C1	1.378 (4)	C6—C1	1.357 (7)
C1—C2	1.392 (5)	C4—N1	1.425 (4)
C2—C3	1.387 (4)	N1—C7	1.323 (7)
C3—C4	1.359 (7)	C7—O2	1.236 (6)
C4—C5	1.401 (5)	C7—C8	1.496 (4)
C5—C6	1.387 (4)
O1—C1—C2	121.1 (4)	C5—C6—C1	121.5 (3)
C1—C2—C3	118.1 (4)	C6—C1—O1	118.2 (3)
C2—C3—C4	121.2 (4)	C6—C1—C2	120.6 (3)
C3—C4—C5	120.7 (3)	C4—N1—C7	129.6 (4)
C3—C4—N1	116.7 (3)	N1—C7—O2	123.7 (3)
C5—C4—N1	122.6 (4)	N1—C7—C8	116.3 (4)
C4—C5—C6	117.7 (4)	O2—C7—C8	120.0 (5)