Absolute configuration of (R)-synephrine hydro­chloride

The title compound, 2-hydr­oxy-2-(4-hydroxy­phenyl)-N-methyl­ethanaminium chloride, C₉H₁₄NO₂⁺·Cl⁻, has been isolated for the first time from the genus Harrisonia. Its structure is stabilized by extensive intra- and inter­molecular hydrogen bonds of type O—H...O, N—H...O, N—H...Cl and C—H...Cl, resulting in a three-dimensional network. Additional weak π–π stacking inter­actions between adjacent mol­ecules further stabilize the crystal structure.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.006 Å
• R factor = 0.067
• wR factor = 0.120
• Data-to-parameter ratio = 16.1

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT199_ALERT_1_C Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_C Check the Reported _diffrn_ambient_temperature .        293 K
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          6

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           25.00
           From the CIF: _reflns_number_total               1928
           Count of symmetry unique reflns         1164
           Completeness (_total/calc)            165.64%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       764
           Fraction of Friedel pairs measured     0.656
           Are heavy atom types Z>Si present        yes

   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

   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
   1 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 1997); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL, PARST95 (Nardelli, 1995) and PLATON (Spek, 2003).

2-hydroxy-2-(4-hydroxyphenyl)-N-methylethanaminium chloride

Crystal data

C9H14NO2^+·Cl^−	Dx = 1.229 Mg m^−3
Mr = 203.66	Melting point: 508 K
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 6750 reflections
a = 6.7480 (13) Å	θ = 1.7–25.0°
b = 6.9559 (13) Å	µ = 0.32 mm^−1
c = 23.450 (4) Å	T = 293 K
V = 1100.7 (4) Å^3	Needle, colourless
Z = 4	0.58 × 0.06 × 0.05 mm
F(000) = 432

Data collection

Siemens SMART CCD area-detector diffractometer	1928 independent reflections
Radiation source: fine-focus sealed tube	1400 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.058
Detector resolution: 8.33 pixels mm^-1	θmax = 25.0°, θmin = 1.7°
ω scans	h = −8→7
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	k = −8→8
Tmin = 0.837, Tmax = 0.984	l = −27→25
5679 measured reflections

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)] = 0.067	H-atom parameters constrained
wR(F^2) = 0.120	w = 1/[σ^2(Fo^2) + (0.0489P)^2 + 0.1384P] where P = (Fo^2 + 2Fc^2)/3
S = 1.02	(Δ/σ)max < 0.001
1928 reflections	Δρmax = 0.30 e Å^−3
120 parameters	Δρmin = −0.16 e Å^−3
0 restraints	Absolute structure: Flack (1983), with 764 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.07 (14)

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

	x	y	z	Uiso*/Ueq
Cl1	0.78718 (16)	0.32462 (17)	0.19117 (4)	0.0591 (3)
O1	0.5151 (5)	−0.0313 (5)	−0.09781 (10)	0.0681 (10)
H1	0.4391	0.0161	−0.1212	0.102*
O2	0.2186 (6)	−0.1709 (4)	0.15505 (11)	0.0821 (10)
H2	0.1708	−0.2588	0.1362	0.123*
N1	0.2029 (5)	0.1634 (5)	0.21902 (11)	0.0490 (8)
H1A	0.0727	0.1882	0.2151	0.059*
H1B	0.2145	0.0468	0.2354	0.059*
C1	0.2819 (7)	−0.0010 (5)	0.06575 (14)	0.0454 (10)
C2	0.1726 (7)	0.0639 (5)	0.02017 (16)	0.0516 (11)
H2A	0.0463	0.1133	0.0263	0.062*
C3	0.2482 (6)	0.0565 (5)	−0.03480 (15)	0.0524 (12)
H3	0.1733	0.1018	−0.0653	0.063*
C4	0.4334 (7)	−0.0176 (5)	−0.04412 (16)	0.0483 (11)
C5	0.5448 (7)	−0.0821 (6)	0.00103 (15)	0.0548 (12)
H5	0.6708	−0.1323	−0.0051	0.066*
C6	0.4680 (7)	−0.0719 (6)	0.05558 (15)	0.0551 (12)
H6	0.5444	−0.1142	0.0861	0.066*
C7	0.1959 (8)	0.0035 (6)	0.12537 (14)	0.0537 (11)
H7	0.0541	0.0329	0.1226	0.064*
C8	0.2936 (6)	0.1550 (6)	0.16122 (14)	0.0496 (9)
H8A	0.4338	0.1268	0.1647	0.060*
H8B	0.2800	0.2791	0.1428	0.060*
C9	0.2892 (7)	0.3078 (7)	0.25780 (17)	0.0741 (13)
H9A	0.2224	0.3027	0.2939	0.111*
H9B	0.2738	0.4336	0.2415	0.111*
H9C	0.4275	0.2812	0.2632	0.111*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0493 (7)	0.0812 (7)	0.0467 (5)	−0.0056 (6)	−0.0023 (5)	0.0021 (5)
O1	0.086 (3)	0.071 (2)	0.0471 (15)	0.0258 (19)	0.0146 (17)	0.0043 (16)
O2	0.141 (3)	0.0581 (18)	0.0472 (15)	−0.025 (2)	0.0002 (18)	−0.0062 (15)
N1	0.0446 (19)	0.0547 (18)	0.0477 (16)	−0.001 (2)	−0.0013 (15)	−0.0103 (15)
C1	0.051 (3)	0.041 (2)	0.045 (2)	−0.002 (2)	0.000 (2)	−0.0090 (18)
C2	0.049 (3)	0.046 (2)	0.059 (2)	0.006 (2)	0.002 (2)	−0.004 (2)
C3	0.068 (4)	0.045 (2)	0.044 (2)	0.012 (2)	−0.003 (2)	0.0048 (18)
C4	0.065 (3)	0.037 (2)	0.043 (2)	0.007 (2)	0.006 (2)	−0.0017 (19)
C5	0.056 (3)	0.049 (3)	0.059 (3)	0.011 (2)	0.002 (2)	−0.002 (2)
C6	0.067 (4)	0.055 (3)	0.043 (2)	0.005 (3)	−0.009 (2)	−0.005 (2)
C7	0.066 (3)	0.052 (2)	0.043 (2)	−0.010 (3)	−0.003 (2)	−0.004 (2)
C8	0.047 (2)	0.053 (2)	0.049 (2)	−0.003 (2)	0.0045 (19)	−0.0105 (19)
C9	0.072 (3)	0.081 (3)	0.070 (3)	−0.018 (3)	0.006 (2)	−0.041 (2)

Geometric parameters (Å, º)

O1—C4	1.378 (4)	C3—C4	1.369 (5)
O1—H1	0.8200	C3—H3	0.9300
O2—C7	1.407 (5)	C4—C5	1.374 (5)
O2—H2	0.8200	C5—C6	1.382 (5)
N1—C9	1.475 (5)	C5—H5	0.9300
N1—C8	1.488 (4)	C6—H6	0.9300
N1—H1A	0.9000	C7—C8	1.501 (5)
N1—H1B	0.9000	C7—H7	0.9800
C1—C6	1.370 (6)	C8—H8A	0.9700
C1—C2	1.375 (5)	C8—H8B	0.9700
C1—C7	1.514 (5)	C9—H9A	0.9600
C2—C3	1.387 (5)	C9—H9B	0.9600
C2—H2A	0.9300	C9—H9C	0.9600
C4—O1—H1	109.5	C6—C5—H5	120.3
C7—O2—H2	109.5	C1—C6—C5	121.6 (4)
C9—N1—C8	115.2 (3)	C1—C6—H6	119.2
C9—N1—H1A	108.5	C5—C6—H6	119.2
C8—N1—H1A	108.5	O2—C7—C8	106.3 (3)
C9—N1—H1B	108.5	O2—C7—C1	113.4 (3)
C8—N1—H1B	108.5	C8—C7—C1	111.3 (4)
H1A—N1—H1B	107.5	O2—C7—H7	108.6
C6—C1—C2	118.3 (4)	C8—C7—H7	108.6
C6—C1—C7	121.3 (4)	C1—C7—H7	108.6
C2—C1—C7	120.3 (4)	N1—C8—C7	110.9 (3)
C1—C2—C3	120.8 (4)	N1—C8—H8A	109.5
C1—C2—H2A	119.6	C7—C8—H8A	109.5
C3—C2—H2A	119.6	N1—C8—H8B	109.5
C4—C3—C2	119.9 (4)	C7—C8—H8B	109.5
C4—C3—H3	120.1	H8A—C8—H8B	108.0
C2—C3—H3	120.1	N1—C9—H9A	109.5
C3—C4—C5	120.0 (4)	N1—C9—H9B	109.5
C3—C4—O1	122.5 (4)	H9A—C9—H9B	109.5
C5—C4—O1	117.6 (4)	N1—C9—H9C	109.5
C4—C5—C6	119.4 (4)	H9A—C9—H9C	109.5
C4—C5—H5	120.3	H9B—C9—H9C	109.5
C6—C1—C2—C3	0.4 (6)	C4—C5—C6—C1	0.8 (6)
C7—C1—C2—C3	−178.5 (4)	C6—C1—C7—O2	−47.4 (5)
C1—C2—C3—C4	0.5 (6)	C2—C1—C7—O2	131.5 (4)
C2—C3—C4—C5	−0.8 (6)	C6—C1—C7—C8	72.4 (5)
C2—C3—C4—O1	179.0 (4)	C2—C1—C7—C8	−108.7 (5)
C3—C4—C5—C6	0.2 (6)	C9—N1—C8—C7	179.8 (4)
O1—C4—C5—C6	−179.7 (4)	O2—C7—C8—N1	−58.2 (5)
C2—C1—C6—C5	−1.1 (6)	C1—C7—C8—N1	177.9 (3)
C7—C1—C6—C5	177.9 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···Cl1^i	0.82	2.23	3.037 (3)	168
N1—H1A···Cl1^ii	0.90	2.22	3.091 (4)	163
N1—H1B···O2	0.90	2.42	2.769 (4)	103
N1—H1B···Cl1^iii	0.90	2.31	3.161 (3)	157
O2—H2···O1^iv	0.82	2.01	2.825 (5)	171
C8—H8A···Cl1	0.97	2.82	3.603 (4)	138

Symmetry codes: (i) x−1/2, −y+1/2, −z; (ii) x−1, y, z; (iii) −x+1, y−1/2, −z+1/2; (iv) x−1/2, −y−1/2, −z.