Bis(D-phenyl­glycinium) sulfate monohydrate

In the title compound, 2C₈H₁₀NO₂⁺·SO₄²⁻·H₂O, the cations exist as two crystallographically independent mol­ecules in the asymmetric unit. In the crystal, these mol­ecules are linked by the sulfate ion through strong O—H...O hydrogen bonds; the phenyl­glycinium cations, sulfate anion and water mol­ecule are held together by N—H...O and O—H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.007 Å
• R factor = 0.043
• wR factor = 0.133
• Data-to-parameter ratio = 7.1

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

General Notes



REFLT_03
         From the CIF: _diffrn_reflns_theta_max           25.00
         From the CIF: _reflns_number_total               1877
         Count of symmetry unique reflns         1890
         Completeness (_total/calc)             99.31%
         TEST3: Check Friedels for noncentro structure
         Estimate of Friedel pairs measured         0
         Fraction of Friedel pairs measured     0.000
         Are heavy atom types Z>Si present          yes
          WARNING: Large fraction of Friedel related reflns may
                   be needed to determine absolute structure

---

S1. Comment

D-Phenylglycine is an important starting material in the production of semisynthetic penicillins and cephalosporins and its derivatives are used in the synthesis of antitumor drugs and other pharmacological applications (Satyam et al., 1996; Jayasinghe et al., 1994). The crystal structure of D-phenylglycine hydrochloride (Ravichandran et al., 1998) has been reported. In the present study, the phenylglycine with sulfuric acid was undertaken.

The asymmetric unit of the title compound, (I), consists of two crystallographically independent protonated phenylglycinium cations, a sulfate anion and a water molecule. In the phenylglycinium molecules, the O1—C11—C12—N11 and O3—C21—C22—N21 torsion angle of 25.0 (5) and 30.7 (5)°, respectively, show that the orientation of the carboxyl group is influenced by the phenyl substitution at the C^α atoms. In α-glycine (Marsh, 1958) and diglycine hydrochloride (Natarajan et al., 1992), the O1—C11—C12—N11 values are 19.1 and 0.3°, and 16.5°, respectively. The aggregation of hydrophillic zone is along (101) and the hydrophobic zone is along (202).

All the O atoms of the sulfate ion are involved in hydrogen bonding. One of the O atoms (O1D), as acceptor, links two crystallographically independent phenylglycinium molecules through strong hydrogen bonds [2.610 (5) and 2.578 (4) Å], resulting in an increased S1—O1D bond distance [1.505 (3) Å]. A bifurcated hydrogen bond is observed in a amino N atom and water molecule with sulfate O atoms (Jeffrey & Saenger, 1991). A zigzag (Z1) head-to-tail sequence is observed, since N11—H11B···O1(-x + 2, y + 1/2, -z) and N21—H21A···O3(-x + 1, y - 1/2, -z + 1) connects two 2₁-related amino acids (Vijayan, 1988).

S2. Experimental

The title compound was crystallized by the slow evaporation of an aqueous solution of D-phenylglycine and sulfuric acid in a stoichiometric ratio of 2:1. Colourless needle-shaped transparent crystals were obtained.

S3. Refinement

The H atoms of the water molecule were located from difference Fourier maps and refined, while all the other H atoms were fixed by geometric constraints using HFIX. 91 Friedel pairs were used to determine the Flack parameter.

Computing details

Data collection: CAD-4 Software (Enraf-Nonius, 1989); cell refinement: CAD-4 Software; data reduction: CAD-4 Software; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 1999); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. The structure of (I) with the atom-numbering scheme. Displacement ellipsoids are shown at the 50% probability level (Johnson, 1976).
	Fig. 2. Packing diagram of the molecules viewed down the b axis.

Bis(D-phenylglycinium) sulfate monohydrate

Crystal data

2C8H10NO2^+·SO4^2^−·H2O	F(000) = 440
Mr = 418.42	Dx = 1.427 Mg m^−3 Dm = 1.429 Mg m^−3 Dm measured by flotation
Monoclinic, P21	Mo Kα radiation, λ = 0.71070 Å
a = 12.3201 (12) Å	Cell parameters from 25 reflections
b = 5.9377 (15) Å	θ = 8.3–13.6°
c = 14.2908 (16) Å	µ = 0.22 mm^−1
β = 111.369 (10)°	T = 293 K
V = 973.5 (3) Å^3	Needles, colorless
Z = 2	0.25 × 0.20 × 0.15 mm

Data collection

Enraf-Nonius sealed tube diffractometer	1778 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.044
Graphite monochromator	θmax = 25.0°, θmin = 2.7°
ω–2θ scans	h = −14→13
Absorption correction: ψ scan (North et.al.,1968)	k = 0→7
Tmin = 0.949, Tmax = 0.968	l = 0→16
1968 measured reflections	3 standard reflections every 60 min
1877 independent reflections	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)] = 0.043	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.133	w = 1/[σ^2(Fo^2) + (0.1005P)^2 + 0.3547P] where P = (Fo^2 + 2Fc^2)/3
S = 1.07	(Δ/σ)max = 0.001
1877 reflections	Δρmax = 0.40 e Å^−3
263 parameters	Δρmin = −0.38 e Å^−3
1 restraint	Absolute structure: Flack (1983), 91 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.05 (14)

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
S1	0.81961 (7)	0.97758 (17)	0.74803 (6)	0.0317 (3)
O1A	0.7916 (3)	0.8243 (8)	0.6634 (2)	0.0597 (10)
O1B	0.8547 (3)	1.1969 (6)	0.7224 (3)	0.0544 (9)
O1C	0.9136 (2)	0.8889 (6)	0.8370 (2)	0.0426 (7)
O1D	0.7121 (2)	1.0069 (5)	0.77330 (19)	0.0384 (7)
O1	0.8619 (3)	0.2951 (6)	−0.0271 (2)	0.0485 (8)
O2	0.6907 (2)	0.3879 (7)	−0.1440 (2)	0.0506 (8)
H2	0.6968	0.2634	−0.1665	0.076*
C11	0.7837 (3)	0.4299 (8)	−0.0651 (3)	0.0373 (10)
C12	0.7852 (3)	0.6639 (8)	−0.0240 (3)	0.0352 (9)
H12	0.7530	0.7681	−0.0806	0.042*
N11	0.9091 (3)	0.7255 (7)	0.0319 (3)	0.0414 (8)
H11A	0.9127	0.8634	0.0573	0.062*
H11B	0.9481	0.7222	−0.0097	0.062*
H11C	0.9408	0.6277	0.0816	0.062*
C13	0.7140 (3)	0.6849 (8)	0.0432 (3)	0.0351 (9)
C14	0.6449 (4)	0.8740 (9)	0.0342 (4)	0.0524 (11)
H14	0.6413	0.9842	−0.0131	0.063*
C15	0.5812 (4)	0.8982 (12)	0.0960 (5)	0.0706 (17)
H15	0.5338	1.0237	0.0893	0.085*
C16	0.5878 (4)	0.7371 (13)	0.1672 (4)	0.0649 (17)
H16	0.5460	0.7551	0.2094	0.078*
C17	0.6557 (4)	0.5509 (13)	0.1756 (4)	0.0649 (16)
H17	0.6592	0.4412	0.2231	0.078*
C18	0.7193 (4)	0.5241 (10)	0.1142 (3)	0.0510 (13)
H18	0.7658	0.3972	0.1208	0.061*
OW1	0.0318 (3)	0.5103 (7)	0.8120 (3)	0.0501 (8)
HW1	−0.030 (6)	0.419 (14)	0.773 (5)	0.08 (2)*
HW2	−0.005 (6)	0.612 (17)	0.829 (5)	0.09 (3)*
O3	0.5245 (3)	0.6447 (6)	0.4267 (2)	0.0465 (8)
O4	0.4780 (2)	0.3180 (7)	0.3419 (2)	0.0491 (8)
H4	0.4195	0.3858	0.3064	0.074*
C21	0.5420 (3)	0.4508 (8)	0.4145 (3)	0.0347 (9)
C22	0.6484 (3)	0.3243 (7)	0.4858 (2)	0.0296 (8)
H22	0.6266	0.1665	0.4887	0.036*
N21	0.6792 (2)	0.4244 (6)	0.5883 (2)	0.0345 (8)
H21A	0.6180	0.4159	0.6071	0.052*
H21B	0.6993	0.5680	0.5869	0.052*
H21C	0.7387	0.3488	0.6317	0.052*
C23	0.7482 (3)	0.3319 (8)	0.4479 (3)	0.0331 (8)
C24	0.7621 (4)	0.1522 (9)	0.3928 (3)	0.0461 (10)
H24	0.7136	0.0276	0.3834	0.055*
C25	0.8476 (4)	0.1540 (11)	0.3512 (4)	0.0580 (13)
H25	0.8572	0.0310	0.3147	0.070*
C26	0.9190 (4)	0.3433 (12)	0.3648 (3)	0.0563 (14)
H26	0.9758	0.3477	0.3362	0.068*
C27	0.9058 (4)	0.5224 (11)	0.4201 (3)	0.0548 (14)
H27	0.9546	0.6467	0.4299	0.066*
C28	0.8195 (3)	0.5195 (9)	0.4617 (3)	0.0439 (11)
H28	0.8099	0.6422	0.4984	0.053*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0309 (4)	0.0326 (5)	0.0258 (4)	0.0008 (4)	0.0034 (3)	−0.0018 (4)
O1A	0.0614 (19)	0.072 (2)	0.0495 (18)	−0.014 (2)	0.0249 (16)	−0.026 (2)
O1B	0.0408 (15)	0.050 (2)	0.0562 (18)	−0.0052 (15)	−0.0017 (14)	0.0155 (17)
O1C	0.0360 (13)	0.0475 (17)	0.0379 (14)	0.0128 (14)	0.0058 (11)	0.0084 (14)
O1D	0.0274 (12)	0.0449 (18)	0.0343 (12)	−0.0043 (13)	0.0010 (10)	−0.0141 (14)
O1	0.0356 (14)	0.052 (2)	0.0464 (16)	0.0065 (14)	0.0012 (12)	−0.0110 (15)
O2	0.0347 (14)	0.057 (2)	0.0454 (16)	0.0087 (15)	−0.0024 (12)	−0.0173 (16)
C11	0.0282 (17)	0.054 (3)	0.0301 (17)	0.0003 (18)	0.0110 (14)	−0.0067 (18)
C12	0.0310 (18)	0.043 (2)	0.0291 (17)	−0.0008 (18)	0.0086 (14)	0.0014 (18)
N11	0.0346 (17)	0.044 (2)	0.0471 (18)	−0.0116 (16)	0.0167 (14)	−0.0114 (18)
C13	0.0288 (17)	0.041 (2)	0.0327 (17)	0.0006 (17)	0.0082 (14)	−0.0034 (17)
C14	0.048 (2)	0.043 (3)	0.068 (3)	0.013 (2)	0.024 (2)	0.007 (3)
C15	0.048 (3)	0.074 (4)	0.095 (4)	0.023 (3)	0.032 (3)	−0.006 (4)
C16	0.044 (2)	0.103 (5)	0.053 (3)	0.009 (3)	0.024 (2)	−0.009 (3)
C17	0.062 (3)	0.090 (5)	0.049 (2)	0.018 (3)	0.028 (2)	0.017 (3)
C18	0.051 (2)	0.059 (4)	0.047 (2)	0.017 (2)	0.024 (2)	0.009 (2)
OW1	0.0441 (16)	0.052 (2)	0.0509 (17)	0.0055 (17)	0.0132 (14)	0.0097 (17)
O3	0.0408 (15)	0.0454 (19)	0.0465 (16)	0.0071 (15)	0.0077 (12)	−0.0034 (15)
O4	0.0352 (14)	0.056 (2)	0.0389 (15)	0.0081 (15)	−0.0067 (12)	−0.0056 (15)
C21	0.0265 (16)	0.047 (3)	0.0301 (17)	0.0017 (18)	0.0100 (14)	0.0019 (18)
C22	0.0255 (15)	0.0303 (19)	0.0283 (16)	−0.0032 (15)	0.0042 (13)	−0.0027 (15)
N21	0.0310 (14)	0.040 (2)	0.0289 (14)	0.0008 (13)	0.0071 (12)	0.0003 (13)
C23	0.0268 (16)	0.040 (2)	0.0265 (16)	0.0061 (16)	0.0025 (13)	0.0036 (16)
C24	0.047 (2)	0.042 (2)	0.049 (2)	0.002 (2)	0.0172 (19)	−0.004 (2)
C25	0.058 (3)	0.064 (3)	0.060 (3)	0.015 (3)	0.031 (2)	−0.009 (3)
C26	0.040 (2)	0.088 (4)	0.045 (2)	0.010 (3)	0.0211 (19)	0.000 (3)
C27	0.037 (2)	0.074 (4)	0.052 (2)	−0.012 (2)	0.0149 (19)	−0.001 (3)
C28	0.041 (2)	0.050 (3)	0.041 (2)	−0.003 (2)	0.0144 (17)	−0.004 (2)

Geometric parameters (Å, º)

S1—O1A	1.451 (4)	C18—H18	0.9300
S1—O1B	1.460 (4)	OW1—HW1	0.94 (8)
S1—O1C	1.470 (3)	OW1—HW2	0.84 (9)
S1—O1D	1.505 (3)	O3—C21	1.196 (6)
O1—C11	1.218 (5)	O4—C21	1.312 (5)
O2—C11	1.305 (5)	O4—H4	0.8200
O2—H2	0.8200	C21—C22	1.533 (5)
C11—C12	1.506 (6)	C22—N21	1.495 (5)
C12—N11	1.488 (5)	C22—C23	1.514 (5)
C12—C13	1.523 (5)	C22—H22	0.9800
C12—H12	0.9800	N21—H21A	0.8900
N11—H11A	0.8900	N21—H21B	0.8900
N11—H11B	0.8900	N21—H21C	0.8900
N11—H11C	0.8900	C23—C24	1.374 (6)
C13—C18	1.376 (7)	C23—C28	1.388 (6)
C13—C14	1.387 (7)	C24—C25	1.385 (6)
C14—C15	1.386 (7)	C24—H24	0.9300
C14—H14	0.9300	C25—C26	1.396 (9)
C15—C16	1.377 (9)	C25—H25	0.9300
C15—H15	0.9300	C26—C27	1.369 (8)
C16—C17	1.366 (9)	C26—H26	0.9300
C16—H16	0.9300	C27—C28	1.394 (6)
C17—C18	1.383 (6)	C27—H27	0.9300
C17—H17	0.9300	C28—H28	0.9300
O1A—S1—O1B	110.6 (2)	C13—C18—H18	119.9
O1A—S1—O1C	111.6 (2)	C17—C18—H18	119.9
O1B—S1—O1C	108.95 (19)	HW1—OW1—HW2	100 (6)
O1A—S1—O1D	108.06 (17)	C21—O4—H4	109.5
O1B—S1—O1D	108.89 (19)	O3—C21—O4	127.3 (4)
O1C—S1—O1D	108.60 (16)	O3—C21—C22	122.0 (4)
C11—O2—H2	109.5	O4—C21—C22	110.7 (4)
O1—C11—O2	124.2 (4)	N21—C22—C23	112.9 (3)
O1—C11—C12	122.4 (3)	N21—C22—C21	107.9 (3)
O2—C11—C12	113.3 (4)	C23—C22—C21	110.9 (3)
N11—C12—C11	107.5 (3)	N21—C22—H22	108.3
N11—C12—C13	110.8 (3)	C23—C22—H22	108.3
C11—C12—C13	113.2 (3)	C21—C22—H22	108.3
N11—C12—H12	108.4	C22—N21—H21A	109.5
C11—C12—H12	108.4	C22—N21—H21B	109.5
C13—C12—H12	108.4	H21A—N21—H21B	109.5
C12—N11—H11A	109.5	C22—N21—H21C	109.5
C12—N11—H11B	109.5	H21A—N21—H21C	109.5
H11A—N11—H11B	109.5	H21B—N21—H21C	109.5
C12—N11—H11C	109.5	C24—C23—C28	120.0 (4)
H11A—N11—H11C	109.5	C24—C23—C22	118.0 (4)
H11B—N11—H11C	109.5	C28—C23—C22	121.9 (4)
C18—C13—C14	119.5 (4)	C23—C24—C25	120.9 (5)
C18—C13—C12	121.6 (4)	C23—C24—H24	119.6
C14—C13—C12	118.9 (4)	C25—C24—H24	119.6
C15—C14—C13	119.7 (5)	C24—C25—C26	119.0 (5)
C15—C14—H14	120.1	C24—C25—H25	120.5
C13—C14—H14	120.1	C26—C25—H25	120.5
C16—C15—C14	120.3 (5)	C27—C26—C25	120.3 (4)
C16—C15—H15	119.9	C27—C26—H26	119.9
C14—C15—H15	119.9	C25—C26—H26	119.9
C17—C16—C15	119.8 (4)	C26—C27—C28	120.4 (5)
C17—C16—H16	120.1	C26—C27—H27	119.8
C15—C16—H16	120.1	C28—C27—H27	119.8
C16—C17—C18	120.5 (5)	C23—C28—C27	119.4 (4)
C16—C17—H17	119.7	C23—C28—H28	120.3
C18—C17—H17	119.7	C27—C28—H28	120.3
C13—C18—C17	120.1 (5)
O1—C11—C12—N11	25.0 (5)	O3—C21—C22—N21	30.7 (5)
O2—C11—C12—N11	−155.6 (3)	O4—C21—C22—N21	−149.7 (3)
O1—C11—C12—C13	−97.7 (5)	O3—C21—C22—C23	−93.4 (4)
O2—C11—C12—C13	81.8 (4)	O4—C21—C22—C23	86.1 (4)
N11—C12—C13—C18	−77.3 (5)	N21—C22—C23—C24	142.7 (4)
C11—C12—C13—C18	43.6 (5)	C21—C22—C23—C24	−96.1 (4)
N11—C12—C13—C14	100.9 (5)	N21—C22—C23—C28	−41.6 (5)
C11—C12—C13—C14	−138.3 (4)	C21—C22—C23—C28	79.6 (4)
C18—C13—C14—C15	−0.6 (7)	C28—C23—C24—C25	0.6 (7)
C12—C13—C14—C15	−178.8 (5)	C22—C23—C24—C25	176.3 (4)
C13—C14—C15—C16	1.0 (9)	C23—C24—C25—C26	−0.8 (7)
C14—C15—C16—C17	−1.2 (9)	C24—C25—C26—C27	1.1 (8)
C15—C16—C17—C18	0.9 (9)	C25—C26—C27—C28	−1.2 (8)
C14—C13—C18—C17	0.3 (7)	C24—C23—C28—C27	−0.6 (6)
C12—C13—C18—C17	178.4 (5)	C22—C23—C28—C27	−176.2 (4)
C16—C17—C18—C13	−0.5 (8)	C26—C27—C28—C23	1.0 (7)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···O1D^i	0.82	1.79	2.610 (5)	174
O4—H4···O1D^ii	0.82	1.76	2.578 (4)	175
N11—H11A···OW1^iii	0.89	1.95	2.680 (6)	139
N11—H11B···O1^iv	0.89	2.25	2.877 (6)	128
N11—H11B···O1C^v	0.89	2.30	2.969 (5)	132
N11—H11C···O1C^vi	0.89	2.25	3.049 (5)	149
N21—H21A···O3^ii	0.89	2.30	2.951 (5)	130
N21—H21B···O1A	0.89	1.97	2.761 (5)	147
N21—H21C···O1B^vii	0.89	1.78	2.674 (5)	178
OW1—HW2···O1C^viii	0.84 (9)	1.95 (9)	2.771 (5)	164 (7)
OW1—HW1···O1B^ix	0.94 (7)	1.88 (8)	2.798 (6)	167 (7)

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