(2S,4R)-4-Fluoro-pyrrolidinium-2-carboxyl-ate.

The crystal structure of the title compound, C(5)H(8)FNO(2), at 100 K, displays inter-molecular N-H⋯O hydrogen bonding between the ammonium and carboxyl-ate groups as a result of its zwitterionic nature in the solid state. The five-membered ring adopts an envelope conformation with the C atom at the 3-position as the flap. The compound is of inter-est with respect to the synthesis and structural properties of synthetic collagens. The absolute structure was determined by comparison with the commercially available material.

Related literature

For the synthesis of the title compound, see: Gottlieb et al. (1965 ▶); Azad et al. (2012 ▶). For its applications and properties with respect to synthetic collagens, see: Hodges & Raines (2003 ▶, 2005 ▶); Holmgren et al. (1999 ▶); Kim et al. (2005 ▶); Mooney et al. (2002 ▶); Persikov et al. (2003 ▶); Raines (2005 ▶); Shoulders & Raines (2009 ▶); Shoulders et al. (2006 ▶); Takeuchi & Prockop (1969 ▶).

Experimental

Crystal data

C5H8FNO2

M = 133.12

Orthorhombic,

a = 7.6530 (6) Å

b = 8.4128 (6) Å

c = 8.6286 (6) Å

V = 555.54 (7) Å3

Z = 4

Mo Kα radiation

μ = 0.14 mm−1

T = 100 K

0.26 × 0.05 × 0.03 mm

Data collection

Oxford Diffraction Gemini Ultra diffractometer

Absorption correction: Gaussian (CrysAlis PRO; Agilent, 2011 ▶) T min = 0.977, T max = 0.996

10227 measured reflections

959 independent reflections

832 reflections with I > 2σ(I)

R int = 0.082

Refinement

R[F 2 > 2σ(F 2)] = 0.038

wR(F 2) = 0.073

S = 1.07

959 reflections

114 parameters

All H-atom parameters refined

Δρmax = 0.32 e Å−3

Δρmin = −0.23 e Å−3

Data collection: CrysAlis PRO (Agilent, 2011 ▶); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: OLEX2 (Dolomanov et al., 2009 ▶); software used to prepare material for publication: OLEX2.

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536812031741/im2392sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812031741/im2392Isup2.hkl

Supplementary material file. DOI: 10.1107/S1600536812031741/im2392Isup3.cdx

Supplementary material file. DOI: 10.1107/S1600536812031741/im2392Isup4.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Enhanced figure: interactive version of Fig. 1

C5H8FNO2	Dx = 1.592 Mg m−3
Mr = 133.12	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, P212121	Cell parameters from 1887 reflections
a = 7.6530 (6) Å	θ = 3.6–30.0°
b = 8.4128 (6) Å	µ = 0.14 mm−1
c = 8.6286 (6) Å	T = 100 K
V = 555.54 (7) Å3	Prism, clear light colourless
Z = 4	0.26 × 0.05 × 0.03 mm
F(000) = 280

Oxford Diffraction Gemini Ultra diffractometer	959 independent reflections
Radiation source: fine-focus sealed tube, fine-focus sealed tube	832 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.082
Detector resolution: 16.0122 pixels mm-1	θmax = 30.1°, θmin = 3.6°
phi and ω scans	h = −10→10
Absorption correction: gaussian (CrysAlis PRO; Agilent, 2011)	k = −11→11
Tmin = 0.977, Tmax = 0.996	l = −12→12
10227 measured reflections

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.038	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.073	All H-atom parameters refined
S = 1.07	w = 1/[σ2(Fo2) + (0.0203P)2 + 0.2288P] where P = (Fo2 + 2Fc2)/3
959 reflections	(Δ/σ)max < 0.001
114 parameters	Δρmax = 0.32 e Å−3
0 restraints	Δρmin = −0.23 e Å−3

Experimental. Recrystallized from 50/50 acetone/water.Absorption correction: CrysAlisPro, Agilent Technologies, Version 1.171.34.49 (release 20-01-2011 CrysAlis171 .NET) (compiled Jan 20 2011,15:58:25) Numerical absorption correction based on gaussian integration over a multifaceted crystal model

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.

	x	y	z	Uiso*/Ueq
F1	0.24111 (16)	0.73474 (16)	0.53792 (14)	0.0194 (3)
O2	0.58809 (19)	0.59578 (17)	0.07960 (17)	0.0143 (3)
O3	0.4982 (2)	0.82996 (18)	−0.01402 (17)	0.0177 (3)
N6	0.2662 (2)	0.8837 (2)	0.2162 (2)	0.0109 (3)
C4	0.3974 (3)	0.7510 (2)	0.2345 (2)	0.0104 (4)
C5	0.5019 (3)	0.7239 (2)	0.0854 (2)	0.0104 (4)
C7	0.1571 (3)	0.6913 (3)	0.3970 (2)	0.0130 (4)
C8	0.1078 (3)	0.8427 (3)	0.3133 (2)	0.0124 (4)
C9	0.2903 (3)	0.6117 (3)	0.2947 (2)	0.0137 (4)
H4	0.480 (3)	0.787 (3)	0.317 (3)	0.010 (6)*
H8A	0.011 (3)	0.822 (3)	0.247 (3)	0.013 (6)*
H7	0.056 (3)	0.629 (3)	0.424 (3)	0.011 (6)*
H8B	0.084 (3)	0.927 (3)	0.387 (3)	0.008 (6)*
H9A	0.233 (3)	0.560 (3)	0.208 (3)	0.020 (7)*
H9B	0.358 (3)	0.540 (3)	0.353 (3)	0.022 (7)*
H6A	0.231 (3)	0.895 (3)	0.115 (3)	0.026 (7)*
H6B	0.314 (3)	0.975 (3)	0.256 (3)	0.020 (7)*

	U11	U22	U33	U12	U13	U23
F1	0.0170 (6)	0.0320 (8)	0.0092 (6)	0.0011 (6)	0.0006 (5)	0.0004 (5)
O2	0.0151 (7)	0.0142 (7)	0.0136 (7)	0.0048 (6)	0.0027 (6)	0.0023 (6)
O3	0.0248 (8)	0.0158 (7)	0.0124 (7)	0.0051 (7)	0.0053 (7)	0.0031 (6)
N6	0.0115 (8)	0.0101 (8)	0.0112 (8)	0.0008 (7)	0.0000 (7)	−0.0014 (7)
C4	0.0110 (8)	0.0110 (9)	0.0091 (8)	0.0004 (8)	−0.0003 (7)	−0.0002 (8)
C5	0.0094 (8)	0.0113 (9)	0.0106 (8)	−0.0034 (8)	0.0000 (7)	−0.0015 (8)
C7	0.0119 (9)	0.0158 (10)	0.0114 (9)	−0.0018 (8)	0.0018 (8)	−0.0003 (8)
C8	0.0106 (9)	0.0153 (9)	0.0112 (9)	0.0017 (8)	0.0007 (8)	−0.0022 (8)
C9	0.0149 (10)	0.0118 (9)	0.0144 (10)	0.0009 (8)	0.0013 (8)	0.0035 (9)

F1—C7	1.423 (2)	C4—H4	1.00 (2)
O2—C5	1.265 (2)	C7—C8	1.512 (3)
O3—C5	1.238 (2)	C7—C9	1.505 (3)
N6—C4	1.509 (3)	C7—H7	0.96 (2)
N6—C8	1.513 (3)	C8—H8A	0.95 (3)
N6—H6A	0.91 (3)	C8—H8B	0.97 (2)
N6—H6B	0.92 (3)	C9—H9A	0.97 (3)
C4—C5	1.532 (3)	C9—H9B	0.94 (3)
C4—C9	1.521 (3)
C4—N6—C8	107.85 (15)	F1—C7—H7	107.3 (14)
C4—N6—H6A	111.6 (17)	C8—C7—H7	111.6 (13)
C4—N6—H6B	108.2 (15)	C9—C7—C8	105.27 (17)
C8—N6—H6A	108.5 (17)	C9—C7—H7	116.6 (14)
C8—N6—H6B	107.5 (15)	N6—C8—H8A	109.4 (15)
H6A—N6—H6B	113 (2)	N6—C8—H8B	110.1 (13)
N6—C4—C5	111.70 (16)	C7—C8—N6	104.86 (16)
N6—C4—C9	104.28 (16)	C7—C8—H8A	109.3 (15)
N6—C4—H4	105.8 (13)	C7—C8—H8B	110.5 (13)
C5—C4—H4	108.2 (13)	H8A—C8—H8B	112.4 (19)
C9—C4—C5	116.93 (17)	C4—C9—H9A	108.9 (15)
C9—C4—H4	109.3 (13)	C4—C9—H9B	112.4 (15)
O2—C5—C4	115.64 (17)	C7—C9—C4	102.86 (17)
O3—C5—O2	126.79 (19)	C7—C9—H9A	110.3 (15)
O3—C5—C4	117.53 (18)	C7—C9—H9B	110.2 (15)
F1—C7—C8	107.72 (17)	H9A—C9—H9B	112 (2)
F1—C7—C9	108.03 (17)

D—H···A	D—H	H···A	D···A	D—H···A
N6—H6B···O2i	0.92 (3)	1.90 (3)	2.744 (2)	152 (2)
N6—H6A···O2ii	0.91 (3)	2.01 (3)	2.899 (2)	164 (2)

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N6—H6B⋯O2i	0.92 (3)	1.90 (3)	2.744 (2)	152 (2)
N6—H6A⋯O2ii	0.91 (3)	2.01 (3)	2.899 (2)	164 (2)

Symmetry codes: (i) ; (ii) .