d-(−)-2-Aza­niumyl-2-(4-hy­droxy­phen­yl)acetate: an ortho­rhom­bic polymorph

Zhang, X.; Yu, Y.; Li, Z.; Li, W.

doi:10.1107/S2414314616007689

organic compounds

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ISSN: 2414-3146

Volume 1| Part 5| May 2016| x160768

doi:10.1107/S2414314616007689

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D-(−)-2-Azaniumyl-2-(4-hydroxyphenyl)acetate: an orthorhombic polymorph

Xiaohui Zhang,^a Yuzhen Yu,^a Zhanjun Li ^a and Wen Li ^b ^*

^aSchool of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou 450001, People's Republic of China, and ^bSchool of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou 450001, People's Republic of China
^*Correspondence e-mail: confidencezzu@139.com

Edited by J. Simpson, University of Otago, New Zealand (Received 5 May 2016; accepted 9 May 2016; online 20 May 2016)

The title compound, C₈H₉NO₃, is the zwitterionic form of D-(−)-4-hydroxyphenylglycine. The plane of the hydroxybenzene ring is inclined at an angle of 88.89 (5)° to the best-fit plane through the five non-H atoms of the aminoacetate substituent. In the crystal, N—H⋯O and O—H⋯O hydrogen bonds link adjacent molecules, forming a three-dimensional network. Weak C—H⋯π interactions are also observed.

Keywords: crystal structure; D-(−)-2-azaniumyl-2-(4-hydroxyphenyl)acetate; D-(−)-4-hydroxyphenylglycine; hydrogen bonding.

CCDC reference: 1478148

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Chemical scheme

Structure description

D-(−)-4-hydroxyphenylglycine (D-HPG) is a key intermediate in the preparation of semi-synthetic antibiotics (Rudolph et al., 2001 ). The crystal structure of a monoclinic polymorph of D-(−)-amino-(4-hydroxyphenyl) acetate has been reported previously in the space group P2₁ (Báthori & Bourne, 2009 ). For the crystal structures of other related compounds, see for example the structures of (p-hydroxyphenyl)glycine(−)-4-(2-chloro-phenyl)-5,5-dimethyl-2-hydroxy-1,3,2-dioxaphosphorinane 2-oxide (Ten Hoeve & Wynberg, 1985 ) and D-p-hydroxyphenylglycine (−)-1-phenylethanesulfonate (Yoshioka et al., 1994 ). Here we report the crystal structure of D-(−)-amino-(4-hydroxyphenyl)acetate in the orthorhombic space group P2₁2₁2₁. Although there is no heavy atom in the structure, the absolute configuration could be well determined by the Flack parameter [0.03 (11)]. However, crystals were grown from a commercial sample of D-(−)-4-hydroxyphenylglycine and the absolute structure assigned on that basis.

As shown in Fig. 1, the reported compound is a zwitterion with the carboxylic acid of the glycine moiety deprotonated and the amino group protonated. The hydroxybenzene ring plane approximately bisects the N1—C7—C8 angle and the plane of the hydroxybenzene ring is inclined at an angle of 88.89 (5) ° to the best fit plane through the five non-hydrogen atoms of the aminoacetate substituent.

Figure 1
View of the title compound, showing the atom-numbering scheme. Displacement ellipsoids for non-H atoms are drawn at the 50% probability level.

In the crystal, adjacent molecules are linked by N—H⋯O and O—H⋯O hydrogen bonds, and a weak C—H⋯π interaction into a three-dimensional network, Fig. 2 and Table 1.

Table 1
Hydrogen-bond geometry (Å, °)

Cg is the centroid of the C1–C6 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O1ⁱ	0.89	2.02	2.838 (2)	153
N1—H1B⋯O2ⁱⁱ	0.89	1.96	2.811 (2)	160
N1—H1C⋯O3ⁱⁱⁱ	0.89	1.87	2.759 (2)	172
O1—H1D⋯O3^iv	0.82	1.81	2.591 (2)	158
C2—H2⋯Cg^v	0.93	3.17	3.913 (2)	139
Symmetry codes: (i) $[-x+{\script{3\over 2}}, -y+1, z-{\script{1\over 2}}]$ ; (ii) $[x-{\script{1\over 2}}, -y+{\script{3\over 2}}, -z+1]$ ; (iii) x-1, y, z; (iv) $[-x+2, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]$ ; (v) $[-x, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Figure 2
The packing diagram of the title compound, viewed along the b axis.

Synthesis and crystallization

1.2 g D-(−)-4-hydroxyphenylglycine (Aldrich, 22818–40-2) was stirred into 40 ml of water at 55°C to prepare a saturated solution. Colourless block-like crystals of the title compound were grown by slow evaporation of this solution at 1°C.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	C₈H₉NO₃
M_r	167.16
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	293
a, b, c (Å)	5.83624 (17), 8.4245 (3), 17.0381 (5)
V (Å³)	837.72 (4)
Z	4
Radiation type	Cu Kα
μ (mm⁻¹)	0.86
Crystal size (mm)	0.2 × 0.19 × 0.16

Data collection
Diffractometer	Agilent Xcalibur Eos Gemini
Absorption correction	Multi-scan (CrysAlis PRO; Agilent, 2012 )
T_min, T_max	0.861, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	3647, 1613, 1570
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.613

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.033, 0.096, 1.05
No. of reflections	1613
No. of parameters	112
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.34, −0.17
Absolute structure	Flack x determined using 616 quotients [(I⁺)−(I⁻)]/[(I⁺)+(I⁻)] (Parsons et al., 2013 )
Absolute structure parameter	0.03 (11)
Computer programs: CrysAlis PRO (Agilent, 2012), SHELXS97 (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ) and OLEX2 (Dolomanov et al., 2009 ).

Structural data

CCDC reference: 1478148

Crystal structure: contains datablock I. DOI: 10.1107/S2414314616007689/sj4032sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S2414314616007689/sj4032Isup2.hkl

Supporting information file. DOI: 10.1107/S2414314616007689/sj4032Isup3.cml

checkCIF report

Synthesis and crystallization top

1.2g D-(-)-4-hydroxyphenylglycine (Aldrich, 22818-40-2) was stirred into 40 ml of water at 55 °C to prepare a saturated solution. Colourless block-like crystals of the title compound were grown by slow evaporation of this solution at 1 °C.

Refinement top

Crystal data, data collection and structure refinement details are summarized in Table 1

Experimental top

1.2 g D-(-)-4-hydroxyphenylglycine (Aldrich, 22818–40-2) was stirred into 40 ml of water at 55°C to prepare a saturated solution. Colourless block-like crystals of the title compound were grown by slow evaporation of this solution at 1°C.

Structure description top

D-(-)-4-hydroxyphenylglycine (D-HPG) is a key intermediate in the preparation of semi-synthetic antibiotics (Rudolph et al., 2001). The crystal structure of a monoclinic polymorph of D-(-)-amino-(4-hydroxyphenyl) acetate has been reported previously in the space group P2₁ (Báthori & Bourne, 2009). For the crystal structures of other related compounds, see for example the structures of (p-hydroxyphenyl)glycine(-)-4-(2-chloro-phenyl)-5,5-dimethyl-2- hydroxy-1,3,2-dioxaphosphorinane 2-oxide (Ten Hoeve & Wynberg, 1985) and D-p-hydroxyphenylglycine (-)-1-phenylethanesulfonate (Yoshioka et al., 1994). Here we report the crystal structure of D-(-)-amino-(4-hydroxyphenyl)acetate in the orthorhombic spacegroup P2₁2₁2₁. With no heavy atom in the structure the absolute configuration could not be clearly established from anomalous scattering effects. However, crystals were grown from a commercial sample of D-(-)-4-hydroxyphenylglycine and the absolute structure assigned on that basis.

As shown in Fig.1, the reported compound is a zwitterion with the carboxylic acid of the glycine moiety deprotonated and the amino group protonated. The hydroxybenzene ring plane approximately bisects the N1—C7—C8 angle and the plane of the hydroxybenzene ring is inclined at an angle of 88.89 (5) ° to the best fit plane through the five non-hydrogen atoms of the aminoacetate substituent.

In the crystal, adjacent molecules are linked by N—H···O and O—H···O hydrogen bonds, and a weak C—H···π interaction into a three-dimensional network, Fig. 2 and Table 1.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO (Agilent, 2012); data reduction: CrysAlis PRO (Agilent, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Figures top

	Fig. 1. View of the title compound, showing the atom-numbering scheme. Displacement ellipsoids for non-H atoms are drawn at the 50% probability level.
	Fig. 2. The packing diagram of the title compound, viewed along the b axis.

D-(-)-2-Azaniumyl-2-(4-hydroxyphenyl)acetate top

Crystal data top

C₈H₉NO₃	D_x = 1.325 Mg m⁻³
M_r = 167.16	Cu Kα radiation, λ = 1.54184 Å
Orthorhombic, P2₁2₁2₁	Cell parameters from 2415 reflections
a = 5.83624 (17) Å	θ = 5.2–70.8°
b = 8.4245 (3) Å	µ = 0.86 mm⁻¹
c = 17.0381 (5) Å	T = 293 K
V = 837.72 (4) Å³	Block, colourless
Z = 4	0.2 × 0.19 × 0.16 mm
F(000) = 352

Data collection top

Agilent Xcalibur Eos Gemini diffractometer	1613 independent reflections
Radiation source: Enhance (Cu) X-ray Source	1570 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.031
Detector resolution: 16.2312 pixels mm^-1	θ_max = 70.9°, θ_min = 5.2°
ω scans	h = −7→6
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2012)	k = −10→10
T_min = 0.861, T_max = 1.000	l = −17→20
3647 measured reflections

Refinement top

Refinement on F²	H-atom parameters constrained
Least-squares matrix: full	w = 1/[σ²(F_o²) + (0.0615P)² + 0.1107P] where P = (F_o² + 2F_c²)/3
R[F² > 2σ(F²)] = 0.033	(Δ/σ)_max < 0.001
wR(F²) = 0.096	Δρ_max = 0.34 e Å⁻³
S = 1.05	Δρ_min = −0.17 e Å⁻³
1613 reflections	Extinction correction: SHELXL2014 (Sheldrick, 2015), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
112 parameters	Extinction coefficient: 0.076 (5)
0 restraints	Absolute structure: Flack x determined using 616 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons et al., 2013)
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.03 (11)
Hydrogen site location: inferred from neighbouring sites

Crystal data top

C₈H₉NO₃	V = 837.72 (4) Å³
M_r = 167.16	Z = 4
Orthorhombic, P2₁2₁2₁	Cu Kα radiation
a = 5.83624 (17) Å	µ = 0.86 mm⁻¹
b = 8.4245 (3) Å	T = 293 K
c = 17.0381 (5) Å	0.2 × 0.19 × 0.16 mm

Data collection top

Agilent Xcalibur Eos Gemini diffractometer	1613 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2012)	1570 reflections with I > 2σ(I)
T_min = 0.861, T_max = 1.000	R_int = 0.031
3647 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.033	H-atom parameters constrained
wR(F²) = 0.096	Δρ_max = 0.34 e Å⁻³
S = 1.05	Δρ_min = −0.17 e Å⁻³
1613 reflections	Absolute structure: Flack x determined using 616 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons et al., 2013)
112 parameters	Absolute structure parameter: 0.03 (11)
0 restraints

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
C1	0.8218 (4)	0.6736 (2)	0.67248 (12)	0.0355 (5)
H1	0.8643	0.7484	0.6351	0.043*
C2	0.7995 (4)	0.7195 (3)	0.75027 (12)	0.0369 (5)
H2	0.8267	0.8242	0.7648	0.044*
C3	0.7367 (4)	0.6088 (3)	0.80590 (11)	0.0329 (5)
C4	0.6892 (5)	0.4543 (3)	0.78378 (12)	0.0424 (6)
H4	0.6415	0.3806	0.8210	0.051*
C5	0.7130 (4)	0.4097 (2)	0.70566 (12)	0.0355 (5)
H5	0.6822	0.3055	0.6911	0.043*
C6	0.7817 (3)	0.5177 (2)	0.64934 (10)	0.0264 (4)
C7	0.8146 (3)	0.4675 (2)	0.56526 (10)	0.0250 (4)
H7	0.7981	0.3519	0.5622	0.030*
C8	1.0554 (3)	0.5127 (2)	0.53564 (11)	0.0270 (4)
N1	0.6394 (3)	0.5416 (2)	0.51327 (9)	0.0276 (4)
H1A	0.6596	0.5079	0.4642	0.033*
H1B	0.6540	0.6467	0.5148	0.033*
H1C	0.5000	0.5145	0.5296	0.033*
O1	0.7186 (4)	0.6457 (2)	0.88365 (8)	0.0478 (5)
H1D	0.7565	0.7384	0.8905	0.072*
O2	1.0735 (3)	0.62801 (19)	0.49116 (10)	0.0396 (4)
O3	1.2178 (3)	0.4283 (2)	0.56048 (10)	0.0445 (5)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0467 (12)	0.0325 (10)	0.0274 (9)	−0.0062 (9)	0.0064 (9)	0.0043 (8)
C2	0.0468 (12)	0.0329 (10)	0.0310 (10)	−0.0058 (9)	0.0005 (9)	−0.0006 (8)
C3	0.0358 (10)	0.0425 (11)	0.0205 (8)	−0.0008 (8)	−0.0037 (8)	0.0010 (8)
C4	0.0586 (14)	0.0416 (12)	0.0268 (10)	−0.0122 (11)	0.0024 (9)	0.0069 (8)
C5	0.0447 (11)	0.0325 (10)	0.0293 (9)	−0.0092 (9)	0.0017 (8)	0.0014 (8)
C6	0.0216 (8)	0.0330 (9)	0.0244 (9)	−0.0005 (7)	0.0003 (7)	0.0028 (7)
C7	0.0216 (8)	0.0274 (8)	0.0260 (8)	−0.0022 (7)	0.0014 (7)	0.0022 (7)
C8	0.0232 (9)	0.0317 (9)	0.0261 (9)	−0.0017 (7)	0.0027 (7)	0.0011 (7)
N1	0.0235 (7)	0.0347 (8)	0.0247 (7)	−0.0002 (6)	0.0002 (6)	0.0000 (6)
O1	0.0744 (12)	0.0473 (9)	0.0216 (7)	−0.0069 (9)	−0.0020 (8)	0.0002 (6)
O2	0.0347 (8)	0.0366 (8)	0.0474 (9)	−0.0045 (7)	0.0063 (7)	0.0119 (6)
O3	0.0237 (7)	0.0589 (10)	0.0510 (9)	0.0039 (7)	0.0020 (6)	0.0199 (7)

Geometric parameters (Å, º) top

C1—H1	0.9300	C6—C7	1.506 (3)
C1—C2	1.387 (3)	C7—H7	0.9800
C1—C6	1.391 (3)	C7—C8	1.541 (2)
C2—H2	0.9300	C7—N1	1.490 (2)
C2—C3	1.379 (3)	C8—O2	1.237 (2)
C3—C4	1.383 (3)	C8—O3	1.258 (3)
C3—O1	1.365 (2)	N1—H1A	0.8900
C4—H4	0.9300	N1—H1B	0.8900
C4—C5	1.390 (3)	N1—H1C	0.8900
C5—H5	0.9300	O1—H1D	0.8200
C5—C6	1.382 (3)

C2—C1—H1	119.4	C5—C6—C7	120.84 (18)
C2—C1—C6	121.21 (19)	C6—C7—H7	108.5
C6—C1—H1	119.4	C6—C7—C8	111.00 (15)
C1—C2—H2	120.2	C8—C7—H7	108.5
C3—C2—C1	119.6 (2)	N1—C7—C6	111.12 (16)
C3—C2—H2	120.2	N1—C7—H7	108.5
C2—C3—C4	120.14 (18)	N1—C7—C8	109.12 (14)
O1—C3—C2	122.26 (19)	O2—C8—C7	118.21 (16)
O1—C3—C4	117.60 (18)	O2—C8—O3	125.84 (18)
C3—C4—H4	120.2	O3—C8—C7	115.94 (16)
C3—C4—C5	119.67 (19)	C7—N1—H1A	109.5
C5—C4—H4	120.2	C7—N1—H1B	109.5
C4—C5—H5	119.5	C7—N1—H1C	109.5
C6—C5—C4	121.1 (2)	H1A—N1—H1B	109.5
C6—C5—H5	119.5	H1A—N1—H1C	109.5
C1—C6—C7	120.89 (17)	H1B—N1—H1C	109.5
C5—C6—C1	118.26 (18)	C3—O1—H1D	109.5

C1—C2—C3—C4	−2.0 (4)	C4—C5—C6—C7	178.0 (2)
C1—C2—C3—O1	178.0 (2)	C5—C6—C7—C8	−126.0 (2)
C1—C6—C7—C8	53.4 (2)	C5—C6—C7—N1	112.4 (2)
C1—C6—C7—N1	−68.2 (2)	C6—C1—C2—C3	0.1 (4)
C2—C1—C6—C5	1.6 (3)	C6—C7—C8—O2	−104.3 (2)
C2—C1—C6—C7	−177.8 (2)	C6—C7—C8—O3	74.7 (2)
C2—C3—C4—C5	2.3 (4)	N1—C7—C8—O2	18.4 (2)
C3—C4—C5—C6	−0.6 (4)	N1—C7—C8—O3	−162.55 (18)
C4—C5—C6—C1	−1.4 (4)	O1—C3—C4—C5	−177.8 (2)

Hydrogen-bond geometry (Å, º) top

Cg is the centroid of the C1–C6 ring.

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O1ⁱ	0.89	2.02	2.838 (2)	153
N1—H1B···O2ⁱⁱ	0.89	1.96	2.811 (2)	160
N1—H1C···O3ⁱⁱⁱ	0.89	1.87	2.759 (2)	172
O1—H1D···O3^iv	0.82	1.81	2.591 (2)	158
C2—H2···Cg^v	0.93	3.17	3.913 (2)	139

Symmetry codes: (i) −x+3/2, −y+1, z−1/2; (ii) x−1/2, −y+3/2, −z+1; (iii) x−1, y, z; (iv) −x+2, y+1/2, −z+3/2; (v) −x, y+1/2, −z+3/2.

Hydrogen-bond geometry (Å, º) top

Cg is the centroid of the C1–C6 ring.

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O1ⁱ	0.89	2.02	2.838 (2)	153.0
N1—H1B···O2ⁱⁱ	0.89	1.96	2.811 (2)	160.0
N1—H1C···O3ⁱⁱⁱ	0.89	1.87	2.759 (2)	172.0
O1—H1D···O3^iv	0.82	1.81	2.591 (2)	158.3
C2—H2···Cg^v	0.93	3.165	3.913 (2)	138.8

Symmetry codes: (i) −x+3/2, −y+1, z−1/2; (ii) x−1/2, −y+3/2, −z+1; (iii) x−1, y, z; (iv) −x+2, y+1/2, −z+3/2; (v) −x, y+1/2, −z+3/2.

Experimental details

Crystal data
Chemical formula	C₈H₉NO₃
M_r	167.16
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	293
a, b, c (Å)	5.83624 (17), 8.4245 (3), 17.0381 (5)
V (Å³)	837.72 (4)
Z	4
Radiation type	Cu Kα
µ (mm⁻¹)	0.86
Crystal size (mm)	0.2 × 0.19 × 0.16

Data collection
Diffractometer	Agilent Xcalibur Eos Gemini
Absorption correction	Multi-scan (CrysAlis PRO; Agilent, 2012)
T_min, T_max	0.861, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	3647, 1613, 1570
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.613

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.033, 0.096, 1.05
No. of reflections	1613
No. of parameters	112
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.34, −0.17
Absolute structure	Flack x determined using 616 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons et al., 2013)
Absolute structure parameter	0.03 (11)

Computer programs: CrysAlis PRO (Agilent, 2012), SHELXS97 (Sheldrick, 2008), SHELXL2014 (Sheldrick, 2015), OLEX2 (Dolomanov et al., 2009).

Acknowledgements

The authors are grateful to the Analysis and Testing Center of Zhengzhou University for use of the single-crystal X-ray diffractometer. This work was supported by the Science and Technology Bureau of Henan through the Cooperation Research Project fund (No. 152107000043 for WL), the Education Bureau of Henan for Major Research Project fund (No. 14 A530007 for WL), National Natural Science Foundation of China (project Nos. 81430085, 21372206 and 81172937 for HML), a PhD Educational Award from the Ministry of Education (No. 20134101130001 for HML), and the Graduate Student Science Research Foundation of Zhengzhou University.

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doi:10.1107/S2414314616007689

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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

D-(−)-2-Aza­niumyl-2-(4-hy­dr­oxy­phen­yl)acetate: an ortho­rhom­bic polymorph

Structure description

Synthesis and crystallization

Refinement

Structural data

Acknowledgements

References

organic compounds

D-(−)-2-Azaniumyl-2-(4-hydroxyphenyl)acetate: an orthorhombic polymorph