(R)-1-Phenyl­ethanaminium (S)-4-chloro­mandelate

The absolute configuration of the title complex, C₈H₁₂N⁺·C₈H₆ClO₃⁻ or [R-C₆H₅C(H)CH₃NH₃][S-4-ClC₆H₄C(H)(OH)CO₂], has been confirmed by the structure determination. In the crystal structure, inter­molecular O—H...O and N—H...O hydrogen bonds form a two-dimensional network perpendicular to the c axis.

Key indicators

• Single-crystal X-ray study
• T = 150 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.045
• wR factor = 0.116
• Data-to-parameter ratio = 17.9

checkCIF/PLATON results

No syntax errors found



Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR') is < 0.90
            Tmin and Tmax reported:      0.787     0.984
            Tmin(prime) and Tmax expected:      0.892     0.980
            RR(prime) =      0.879
            Please check that your absorption correction is appropriate.
PLAT061_ALERT_3_C Tmax/Tmin Range Test RR' too Large .............       0.88
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          1
              C8 H12 N

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           27.51
           From the CIF: _reflns_number_total               3431
           Count of symmetry unique reflns         2009
           Completeness (_total/calc)            170.78%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured      1422
           Fraction of Friedel pairs measured     0.708
           Are heavy atom types Z>Si present        yes
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C8     ...          S
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C15    ...          R
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          1

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   3 ALERT level C = Check and explain
   4 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
   3 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

In our previous work, phenylethylamine (PEA) has been proven to be an efficient resolving agent for resolution of racemic 4-chloromandelic acid. In order to further investigate the chiral recognition mechanism, the single-crystal structure of the corresponding more soluble salt, (R)-Phenylethylammonium (S)-4-chloromandelate, is reported here for comparison with that of the less soluble salt (R)-Phenylethylammonium (R)-4-chloromandelate (He et al., 2007).

The title complex consists of an ion pair; an amine cation and a carboxylate anion (see Fig. 1). The absolute stereochemistry of each ion has been confirmed by the structure determination [absolute structure parameter -0.03 (8); (Flack, 1983)]. All three H atoms of the –NH₃ group and the H atom of the O—H group act as hydrogen bond donors in intermolecular O—H···O and N—H···O hydrogen bonds, forming a two-dimensional network perpendicular to the c axis. The hydrogen bond motif in the title compound is different to that observed in the room temperature structure of the R,R diastereomer (He et al., 2007).

Related literature

For background information and the crystal structure of the R,R diastereomer of the title compound, see: He et al. (2007).

S2. Experimental

To a solution (S)-4-chloromandelate (2.0 g, 0.01 mol) in 10 ml 2-propanol, (1.3 mL, 0.01 mol), (R)-Phenylethylammonium, was added gradually. A white crystalline solid appeared. The crystals were collected and washed with 2-propanol twice to give the title compound (1.85 g), yield 56%. Single crystals were grown from a concentrated methanol solution of the title compound by slow evaporation at room temperature.

S3. Refinement

All H atoms were positioned geometrically and constrained as riding atoms with; C—H = 1.00Å and U_iso(H) = 1.2U_eq(C) for methyne H atoms, C—H = 0.98Å and U_iso(H) = 1.5U_eq(C) for methyl H atoms, C—H = 0.95Å and U_iso(H) = 1.2U_eq(C) for aromatic H atoms, O—H = 0.84Å and U_iso(H) = 1.5U_eq(C) for hydroxyl H atoms and N—H = 0.91Å and U_iso(H) = 1.5U_eq(C) for amine H atoms.

Computing details

Data collection: COLLECT (Nonius, 1997); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL/PC (Sheldrick, 2008); software used to prepare material for publication: SHELXTL/PC (Sheldrick, 2008).

Figures

Fig. 1. The molecular structure of the title compound with 30% probability displacement ellipsoids and the atom labelling scheme.

(R)-1-Phenylethanaminium (S)-4-chloromandelate

Crystal data

C8H12N^+·C8H6ClO3^−	F(000) = 324
Mr = 307.76	Dx = 1.295 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 11634 reflections
a = 10.4091 (7) Å	θ = 2.0–27.5°
b = 5.7635 (4) Å	µ = 0.25 mm^−1
c = 13.2544 (10) Å	T = 150 K
β = 96.831 (4)°	Plate, colourless
V = 789.52 (10) Å^3	0.45 × 0.15 × 0.08 mm
Z = 2

Data collection

Nonius KappaCCD diffractometer	3431 independent reflections
Radiation source: fine-focus sealed tube	2881 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.072
ϕ scans, and ω scans with κ offsets	θmax = 27.5°, θmin = 2.4°
Absorption correction: multi-scan (SORTAV; Blessing, 1995)	h = −13→13
Tmin = 0.787, Tmax = 0.984	k = −7→7
7943 measured reflections	l = −16→17

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)] = 0.044	H-atom parameters constrained
wR(F^2) = 0.115	w = 1/[σ^2(Fo^2) + (0.0565P)^2 + 0.1172P] where P = (Fo^2 + 2Fc^2)/3
S = 1.05	(Δ/σ)max < 0.001
3431 reflections	Δρmax = 0.26 e Å^−3
192 parameters	Δρmin = −0.30 e Å^−3
1 restraint	Absolute structure: Flack (1983), 1436 Fridel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.03 (8)

Special details

Experimental. Absorption correction: multi-scan from symmetry-related measurements (SORTAV; Blessing, 1995). M.p. 140.8–142.5 K. The specific rotation was [α]²⁵_D = +50.5° (c=1, C¹H³OH), determined using a Perkin Elmer Model 341 Digital Polarimeter; ¹H-NMR (d₆-DMSO/TMS): δ 1.424 (d, 3H, CH₃), 4.300 (m, 1H, CHNH₂), 4.536 (s, 1H, CHOH), 7.268–7.457 (m, 9H, C₆H₅ and C₆H₄Cl) measured using an INOVA 400 MHz NMR (Varian).

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
Cl1	0.62566 (7)	0.61666 (16)	1.01588 (5)	0.0611 (3)
C2	0.6271 (2)	0.5894 (5)	0.88508 (17)	0.0393 (6)
C3	0.5788 (3)	0.7663 (5)	0.82206 (19)	0.0435 (6)
H3A	0.5408	0.8990	0.8490	0.052*
C4	0.5863 (2)	0.7484 (4)	0.71887 (18)	0.0368 (5)
H4A	0.5529	0.8702	0.6751	0.044*
C5	0.64141 (18)	0.5567 (4)	0.67818 (16)	0.0260 (4)
C6	0.6887 (2)	0.3804 (4)	0.74326 (19)	0.0359 (5)
H6A	0.7267	0.2473	0.7165	0.043*
C7	0.6815 (2)	0.3952 (5)	0.84688 (19)	0.0422 (6)
H7A	0.7137	0.2730	0.8909	0.051*
C8	0.64285 (18)	0.5435 (3)	0.56394 (15)	0.0246 (4)
H8A	0.6574	0.7033	0.5382	0.030*
O9	0.52152 (12)	0.4619 (3)	0.51580 (11)	0.0287 (3)
H9A	0.4701	0.5740	0.5053	0.043*
C10	0.74941 (19)	0.3868 (4)	0.53386 (15)	0.0249 (4)
O11	0.72224 (14)	0.1839 (3)	0.50678 (13)	0.0345 (4)
O12	0.86102 (13)	0.4771 (3)	0.53936 (11)	0.0299 (3)
N13	0.87681 (16)	−0.1239 (3)	0.42117 (14)	0.0269 (4)
H13A	0.8657	−0.2587	0.4548	0.040*
H13B	0.8332	−0.0076	0.4487	0.040*
H13C	0.9625	−0.0885	0.4267	0.040*
C14	0.6876 (2)	−0.2471 (5)	0.30409 (19)	0.0395 (6)
H14A	0.6898	−0.4075	0.3288	0.059*
H14B	0.6480	−0.2430	0.2332	0.059*
H14C	0.6366	−0.1517	0.3458	0.059*
C15	0.8256 (2)	−0.1521 (4)	0.31099 (16)	0.0296 (5)
H15A	0.8223	0.0045	0.2783	0.035*
C16	0.91365 (19)	−0.3052 (4)	0.25701 (17)	0.0278 (5)
C17	0.9388 (2)	−0.2491 (4)	0.15998 (17)	0.0348 (5)
H17A	0.9041	−0.1103	0.1292	0.042*
C18	1.0142 (2)	−0.3926 (5)	0.10662 (18)	0.0425 (6)
H18A	1.0293	−0.3536	0.0394	0.051*
C19	1.0672 (2)	−0.5923 (5)	0.15193 (19)	0.0400 (6)
H19A	1.1194	−0.6903	0.1160	0.048*
C20	1.0443 (2)	−0.6496 (4)	0.24955 (19)	0.0376 (6)
H20A	1.0815	−0.7859	0.2810	0.045*
C21	0.9671 (2)	−0.5080 (4)	0.30114 (17)	0.0325 (5)
H21A	0.9502	−0.5495	0.3677	0.039*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0659 (5)	0.0910 (7)	0.0280 (3)	−0.0131 (4)	0.0120 (3)	−0.0052 (4)
C2	0.0348 (12)	0.0566 (15)	0.0273 (11)	−0.0126 (12)	0.0076 (9)	−0.0033 (12)
C3	0.0474 (15)	0.0465 (15)	0.0389 (14)	0.0067 (12)	0.0141 (11)	−0.0070 (13)
C4	0.0438 (13)	0.0333 (12)	0.0342 (12)	0.0085 (11)	0.0089 (10)	−0.0005 (10)
C5	0.0202 (9)	0.0275 (11)	0.0311 (10)	−0.0025 (8)	0.0058 (8)	−0.0028 (9)
C6	0.0376 (12)	0.0329 (11)	0.0383 (13)	0.0040 (10)	0.0094 (10)	0.0050 (11)
C7	0.0415 (13)	0.0485 (15)	0.0366 (13)	0.0003 (12)	0.0048 (10)	0.0083 (12)
C8	0.0202 (9)	0.0239 (10)	0.0299 (11)	−0.0023 (8)	0.0035 (8)	−0.0004 (8)
O9	0.0199 (7)	0.0278 (8)	0.0376 (9)	0.0015 (6)	0.0000 (6)	−0.0031 (7)
C10	0.0223 (9)	0.0273 (11)	0.0256 (10)	0.0011 (8)	0.0052 (8)	0.0004 (9)
O11	0.0290 (8)	0.0286 (8)	0.0474 (10)	−0.0002 (6)	0.0104 (7)	−0.0071 (7)
O12	0.0208 (7)	0.0323 (8)	0.0373 (8)	−0.0001 (6)	0.0067 (6)	0.0026 (7)
N13	0.0233 (8)	0.0258 (9)	0.0325 (9)	0.0003 (7)	0.0066 (7)	−0.0027 (8)
C14	0.0272 (11)	0.0549 (15)	0.0361 (13)	0.0034 (11)	0.0029 (9)	−0.0099 (12)
C15	0.0290 (11)	0.0321 (12)	0.0284 (11)	0.0066 (9)	0.0063 (9)	0.0001 (9)
C16	0.0226 (10)	0.0298 (11)	0.0314 (11)	−0.0001 (8)	0.0051 (8)	−0.0043 (9)
C17	0.0373 (12)	0.0359 (12)	0.0320 (12)	0.0035 (10)	0.0070 (9)	0.0021 (10)
C18	0.0429 (13)	0.0526 (16)	0.0344 (12)	0.0052 (12)	0.0145 (10)	−0.0043 (12)
C19	0.0304 (11)	0.0468 (15)	0.0442 (14)	0.0054 (10)	0.0105 (10)	−0.0116 (12)
C20	0.0338 (12)	0.0358 (13)	0.0432 (14)	0.0078 (10)	0.0040 (10)	−0.0038 (11)
C21	0.0340 (11)	0.0343 (12)	0.0305 (12)	0.0038 (10)	0.0087 (9)	0.0003 (10)

Geometric parameters (Å, º)

Cl1—C2	1.743 (2)	N13—H13B	0.9100
C2—C3	1.375 (4)	N13—H13C	0.9100
C2—C7	1.378 (4)	C14—C15	1.530 (3)
C3—C4	1.383 (3)	C14—H14A	0.9800
C3—H3A	0.9500	C14—H14B	0.9800
C4—C5	1.384 (3)	C14—H14C	0.9800
C4—H4A	0.9500	C15—C16	1.512 (3)
C5—C6	1.385 (3)	C15—H15A	1.0000
C5—C8	1.518 (3)	C16—C17	1.381 (3)
C6—C7	1.387 (3)	C16—C21	1.393 (3)
C6—H6A	0.9500	C17—C18	1.390 (3)
C7—H7A	0.9500	C17—H17A	0.9500
C8—O9	1.425 (2)	C18—C19	1.382 (4)
C8—C10	1.520 (3)	C18—H18A	0.9500
C8—H8A	1.0000	C19—C20	1.383 (3)
O9—H9A	0.8400	C19—H19A	0.9500
C10—O11	1.246 (3)	C20—C21	1.382 (3)
C10—O12	1.267 (2)	C20—H20A	0.9500
N13—C15	1.503 (3)	C21—H21A	0.9500
N13—H13A	0.9100
C3—C2—C7	121.1 (2)	H13A—N13—H13C	109.5
C3—C2—Cl1	119.5 (2)	H13B—N13—H13C	109.5
C7—C2—Cl1	119.4 (2)	C15—C14—H14A	109.5
C2—C3—C4	119.1 (2)	C15—C14—H14B	109.5
C2—C3—H3A	120.5	H14A—C14—H14B	109.5
C4—C3—H3A	120.5	C15—C14—H14C	109.5
C3—C4—C5	121.3 (2)	H14A—C14—H14C	109.5
C3—C4—H4A	119.3	H14B—C14—H14C	109.5
C5—C4—H4A	119.3	N13—C15—C16	110.97 (17)
C4—C5—C6	118.5 (2)	N13—C15—C14	108.59 (18)
C4—C5—C8	118.86 (19)	C16—C15—C14	112.37 (19)
C6—C5—C8	122.64 (19)	N13—C15—H15A	108.3
C5—C6—C7	121.0 (2)	C16—C15—H15A	108.3
C5—C6—H6A	119.5	C14—C15—H15A	108.3
C7—C6—H6A	119.5	C17—C16—C21	118.5 (2)
C2—C7—C6	119.1 (2)	C17—C16—C15	119.8 (2)
C2—C7—H7A	120.4	C21—C16—C15	121.69 (19)
C6—C7—H7A	120.4	C16—C17—C18	121.0 (2)
O9—C8—C5	110.47 (15)	C16—C17—H17A	119.5
O9—C8—C10	108.78 (16)	C18—C17—H17A	119.5
C5—C8—C10	112.68 (16)	C19—C18—C17	119.6 (2)
O9—C8—H8A	108.3	C19—C18—H18A	120.2
C5—C8—H8A	108.3	C17—C18—H18A	120.2
C10—C8—H8A	108.3	C18—C19—C20	120.1 (2)
C8—O9—H9A	109.5	C18—C19—H19A	120.0
O11—C10—O12	125.27 (19)	C20—C19—H19A	120.0
O11—C10—C8	119.05 (17)	C21—C20—C19	119.8 (2)
O12—C10—C8	115.68 (18)	C21—C20—H20A	120.1
C15—N13—H13A	109.5	C19—C20—H20A	120.1
C15—N13—H13B	109.5	C20—C21—C16	121.0 (2)
H13A—N13—H13B	109.5	C20—C21—H21A	119.5
C15—N13—H13C	109.5	C16—C21—H21A	119.5
C7—C2—C3—C4	−0.5 (4)	C5—C8—C10—O11	98.5 (2)
Cl1—C2—C3—C4	176.8 (2)	O9—C8—C10—O12	155.95 (17)
C2—C3—C4—C5	−0.1 (4)	C5—C8—C10—O12	−81.2 (2)
C3—C4—C5—C6	0.4 (3)	N13—C15—C16—C17	−139.6 (2)
C3—C4—C5—C8	178.0 (2)	C14—C15—C16—C17	98.6 (2)
C4—C5—C6—C7	−0.2 (3)	N13—C15—C16—C21	42.8 (3)
C8—C5—C6—C7	−177.7 (2)	C14—C15—C16—C21	−79.0 (3)
C3—C2—C7—C6	0.8 (4)	C21—C16—C17—C18	0.9 (3)
Cl1—C2—C7—C6	−176.52 (19)	C15—C16—C17—C18	−176.8 (2)
C5—C6—C7—C2	−0.4 (3)	C16—C17—C18—C19	−1.3 (4)
C4—C5—C8—O9	−81.8 (2)	C17—C18—C19—C20	0.5 (4)
C6—C5—C8—O9	95.7 (2)	C18—C19—C20—C21	0.8 (3)
C4—C5—C8—C10	156.32 (19)	C19—C20—C21—C16	−1.2 (3)
C6—C5—C8—C10	−26.2 (3)	C17—C16—C21—C20	0.4 (3)
O9—C8—C10—O11	−24.4 (3)	C15—C16—C21—C20	178.1 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O9—H9A···O9^i	0.84	2.26	2.939 (2)	139
O9—H9A···O11^i	0.84	2.09	2.826 (2)	146
N13—H13A···O12^ii	0.91	1.89	2.798 (2)	172
N13—H13B···O11	0.91	1.83	2.731 (2)	169
N13—H13C···O12^iii	0.91	1.88	2.779 (2)	171

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