Zwitterionic pyrrolidine-2,2-diylbis(phosphonic acid) at 100, 150 and 293 K

The title compound, C₄H₁₁NO₆P₂, reveals a two-dimensional network of P—O—H...O=P and N—H...O=P hydrogen-bond interactions, forming molecular slabs parallel with the (010) plane. One O—H...O interaction is distinct within these sets: whilst forming the shortest intermolecular hydrogen bond, it possesses a short P—O(H) bond of 1.5291 (10) Å. Weak C—H...O contacts link individual stacks to produce a three-dimensional array. The compound is zwitterionic: one H atom from a P—O—H group has transferred to the pyrrolidine ring N atom.

Computing details

For all compounds, data collection: COLLECT (Nonius, 1998); cell refinement: DENZO (Otwinowski & Minor, 1997); data reduction: DENZO; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 1999); software used to prepare material for publication: SHELXL97.

(I) pyrrolidin-2,2-diylbis(phosphonic acid)

Crystal data

C4H11NO6P2	Z = 2
Mr = 231.08	F(000) = 240
Triclinic, P1	Dx = 1.845 Mg m^−3 Dm = 1.85 (2) Mg m^−3 Dm measured by flotation
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.7397 (2) Å	Cell parameters from all reflections
b = 7.7777 (3) Å	θ = 2.4–28.0°
c = 8.5184 (3) Å	µ = 0.52 mm^−1
α = 78.5397 (14)°	T = 100 K
β = 85.6376 (19)°	Plate, colourless
γ = 71.8947 (18)°	0.44 × 0.19 × 0.12 mm
V = 415.91 (2) Å^3

Data collection

Nonius Kappa CCD area detector diffractometer	1897 reflections with I > 2σ(I)
Radiation source: rotating anode	Rint = 0.033
Graphite monochromator	θmax = 28.0°, θmin = 2.4°
φ scans with κ at 0° and ω scans	h = −8→8
9553 measured reflections	k = −10→10
2003 independent reflections	l = −11→11

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.024	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.064	All H-atom parameters refined
S = 1.07	w = 1/[σ^2(Fo^2) + (0.0216P)^2 + 0.3871P] where P = (Fo^2 + 2Fc^2)/3
2003 reflections	(Δ/σ)max = 0.001
162 parameters	Δρmax = 0.48 e Å^−3
0 restraints	Δρmin = −0.40 e Å^−3

Special details

Experimental. The same crystal was measured at three temperatures, 293 K, 150 K and 100 K. For each data set, intensities were measured with a Nonius KappaCCD diffractometer. The initial orientation matrix and cell parameters were obtained by indexing, integrating and refinement of spots on each image using DENZO (Otwinowski & Minor, 1997), and were used to calculate an optimal strategy for data collection. The final unit-cell parameters are obtained by reindexing the collected images using their kappa-geometry orientation matrices as a basis without interframe scaling refinement. Cell parameters were determined by SCALEPACK (Otwinowski & Minor, 1997) using the positions of measured reflections (with θ values varying from 2 to 28°). At 100 K the dataset was 99.7% complete out to 28° in two-theta; at 150 K the completeness was 99.8% out to 27.5° in two-theta, and at 293 K, the data were 99.7% complete out to 27.5° in two-theta.

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
P1	0.19669 (5)	0.16132 (4)	0.51457 (4)	0.00660 (10)
P2	0.26610 (5)	−0.05738 (4)	0.85366 (4)	0.00657 (10)
O3	0.30580 (15)	0.29037 (13)	0.41067 (12)	0.0097 (2)
H3	0.397 (5)	0.247 (5)	0.329 (4)	0.080 (11)*
O4	0.26060 (15)	−0.02999 (13)	1.02530 (11)	0.0093 (2)
O5	0.26564 (15)	−0.03287 (13)	0.48525 (11)	0.00861 (19)
O6	−0.04345 (15)	0.25196 (14)	0.49810 (12)	0.0098 (2)
H6	−0.107 (4)	0.179 (4)	0.496 (3)	0.048 (8)*
O7	0.06574 (15)	−0.09909 (14)	0.81328 (12)	0.0095 (2)
H7	−0.037 (4)	−0.054 (4)	0.870 (3)	0.050 (8)*
O8	0.45994 (15)	−0.20120 (13)	0.81226 (11)	0.0100 (2)
N9	0.45901 (18)	0.20112 (16)	0.73174 (14)	0.0085 (2)
H9A	0.532 (3)	0.131 (3)	0.820 (2)	0.014 (4)*
H9B	0.542 (3)	0.168 (3)	0.644 (3)	0.021 (5)*
C10	0.2503 (2)	0.16582 (18)	0.72339 (15)	0.0073 (2)
C11	0.0891 (2)	0.33095 (18)	0.78713 (16)	0.0095 (3)
H11A	0.005 (3)	0.419 (2)	0.700 (2)	0.010 (4)*
H11B	−0.006 (3)	0.288 (3)	0.867 (2)	0.014 (4)*
C12	0.2207 (2)	0.4254 (2)	0.85727 (18)	0.0134 (3)
H12A	0.263 (3)	0.365 (3)	0.966 (2)	0.017 (5)*
H12B	0.151 (3)	0.551 (3)	0.853 (2)	0.017 (5)*
C13	0.4123 (2)	0.39927 (19)	0.74764 (18)	0.0133 (3)
H13A	0.383 (3)	0.475 (3)	0.641 (2)	0.016 (5)*
H13B	0.531 (3)	0.415 (3)	0.789 (2)	0.019 (5)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
P1	0.00618 (16)	0.00669 (17)	0.00613 (16)	−0.00083 (12)	−0.00034 (12)	−0.00105 (12)
P2	0.00683 (17)	0.00682 (16)	0.00554 (16)	−0.00156 (13)	0.00043 (11)	−0.00094 (11)
O3	0.0109 (5)	0.0094 (4)	0.0080 (4)	−0.0027 (4)	0.0022 (4)	−0.0009 (4)
O4	0.0091 (4)	0.0121 (5)	0.0059 (4)	−0.0022 (4)	0.0002 (3)	−0.0017 (4)
O5	0.0079 (4)	0.0084 (4)	0.0092 (4)	−0.0012 (3)	0.0000 (3)	−0.0026 (3)
O6	0.0072 (5)	0.0091 (5)	0.0125 (5)	−0.0009 (4)	−0.0020 (4)	−0.0027 (4)
O7	0.0088 (5)	0.0117 (5)	0.0093 (5)	−0.0039 (4)	0.0013 (4)	−0.0038 (4)
O8	0.0091 (5)	0.0093 (4)	0.0089 (4)	0.0002 (4)	0.0014 (4)	−0.0007 (4)
N9	0.0077 (5)	0.0094 (5)	0.0084 (5)	−0.0028 (4)	−0.0004 (4)	−0.0015 (4)
C10	0.0067 (6)	0.0078 (6)	0.0073 (6)	−0.0024 (5)	0.0001 (4)	−0.0011 (5)
C11	0.0097 (6)	0.0079 (6)	0.0097 (6)	−0.0003 (5)	0.0005 (5)	−0.0027 (5)
C12	0.0157 (7)	0.0098 (6)	0.0144 (7)	−0.0010 (5)	−0.0023 (5)	−0.0054 (5)
C13	0.0148 (7)	0.0085 (6)	0.0178 (7)	−0.0050 (5)	−0.0020 (6)	−0.0021 (5)

Geometric parameters (Å, º)

P1—O5	1.5018 (10)	N9—C10	1.5236 (16)
P1—O3	1.5291 (10)	N9—H9A	0.91 (2)
P1—O6	1.5563 (10)	N9—H9B	0.93 (2)
P1—C10	1.8511 (13)	C10—C11	1.5637 (18)
P2—O8	1.5036 (10)	C11—C12	1.5313 (19)
P2—O4	1.5150 (10)	C11—H11A	0.980 (18)
P2—O7	1.5602 (10)	C11—H11B	0.978 (19)
P2—C10	1.8423 (13)	C12—C13	1.520 (2)
O3—H3	0.93 (3)	C12—H12A	0.97 (2)
O6—H6	0.81 (3)	C12—H12B	0.94 (2)
O7—H7	0.84 (3)	C13—H13A	0.97 (2)
N9—C13	1.5058 (17)	C13—H13B	0.95 (2)
O5—P1—O3	115.34 (6)	C11—C10—P2	112.56 (9)
O5—P1—O6	112.31 (6)	N9—C10—P1	110.35 (8)
O3—P1—O6	108.44 (6)	C11—C10—P1	111.82 (9)
O5—P1—C10	110.50 (6)	P2—C10—P1	110.54 (7)
O3—P1—C10	104.92 (6)	C12—C11—C10	105.22 (11)
O6—P1—C10	104.54 (6)	C12—C11—H11A	109.1 (11)
O8—P2—O4	113.18 (6)	C10—C11—H11A	111.1 (11)
O8—P2—O7	111.01 (6)	C12—C11—H11B	112.4 (11)
O4—P2—O7	111.48 (5)	C10—C11—H11B	110.8 (11)
O8—P2—C10	109.62 (6)	H11A—C11—H11B	108.2 (15)
O4—P2—C10	107.24 (6)	C13—C12—C11	102.71 (11)
O7—P2—C10	103.81 (6)	C13—C12—H12A	109.4 (11)
P1—O3—H3	119 (2)	C11—C12—H12A	111.9 (11)
P1—O6—H6	113.4 (19)	C13—C12—H12B	110.5 (12)
P2—O7—H7	112.2 (19)	C11—C12—H12B	111.4 (12)
C13—N9—C10	107.20 (10)	H12A—C12—H12B	110.7 (16)
C13—N9—H9A	107.3 (12)	N9—C13—C12	101.71 (11)
C10—N9—H9A	111.6 (12)	N9—C13—H13A	107.9 (11)
C13—N9—H9B	115.0 (13)	C12—C13—H13A	112.6 (11)
C10—N9—H9B	109.6 (13)	N9—C13—H13B	108.9 (12)
H9A—N9—H9B	106.2 (17)	C12—C13—H13B	115.7 (12)
N9—C10—C11	103.81 (10)	H13A—C13—H13B	109.6 (16)
N9—C10—P2	107.47 (8)
C13—N9—C10—C11	−16.74 (13)	O6—P1—C10—N9	−143.82 (8)
C13—N9—C10—P2	−136.18 (9)	O5—P1—C10—C11	−149.86 (9)
C13—N9—C10—P1	103.22 (10)	O3—P1—C10—C11	85.22 (10)
O8—P2—C10—N9	−51.09 (10)	O6—P1—C10—C11	−28.82 (10)
O4—P2—C10—N9	72.15 (9)	O5—P1—C10—P2	−23.60 (8)
O7—P2—C10—N9	−169.74 (8)	O3—P1—C10—P2	−148.52 (6)
O8—P2—C10—C11	−164.77 (9)	O6—P1—C10—P2	97.44 (7)
O4—P2—C10—C11	−41.54 (10)	N9—C10—C11—C12	−10.85 (13)
O7—P2—C10—C11	76.57 (10)	P2—C10—C11—C12	105.06 (11)
O8—P2—C10—P1	69.39 (8)	P1—C10—C11—C12	−129.80 (10)
O4—P2—C10—P1	−167.38 (6)	C10—C11—C12—C13	33.98 (13)
O7—P2—C10—P1	−49.27 (8)	C10—N9—C13—C12	37.99 (13)
O5—P1—C10—N9	95.14 (9)	C11—C12—C13—N9	−43.88 (13)
O3—P1—C10—N9	−29.78 (10)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O8^i	0.93 (3)	1.51 (3)	2.4427 (13)	173 (3)
O6—H6···O5^ii	0.81 (3)	1.77 (3)	2.5737 (14)	172 (3)
O7—H7···O4^iii	0.84 (3)	1.70 (3)	2.5401 (14)	174 (3)
N9—H9A···O4^iv	0.91 (2)	1.87 (2)	2.7501 (15)	161.6 (17)
N9—H9B···O5^i	0.93 (2)	1.84 (2)	2.7392 (15)	161.4 (19)
C12—H12B···O7^v	0.94 (2)	2.56 (2)	3.4666 (18)	163.3 (18)

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

(II) pyrrolidin-2,2-diylbis(phosphonic acid)

Crystal data

C4H11NO6P2	Z = 2
Mr = 231.08	F(000) = 240
Triclinic, P1	Dx = 1.842 Mg m^−3 Dm = 1.85 (2) Mg m^−3 Dm measured by flotation
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.7451 (2) Å	Cell parameters from all reflections
b = 7.7855 (3) Å	θ = 2.4–27.5°
c = 8.5197 (3) Å	µ = 0.52 mm^−1
α = 78.5651 (14)°	T = 150 K
β = 85.6151 (19)°	Plate, colourless
γ = 71.8678 (19)°	0.44 × 0.19 × 0.12 mm
V = 416.69 (3) Å^3

Data collection

Nonius Kappa CCD area detector diffractometer	1800 reflections with I > 2σ(I)
Radiation source: rotating anode	Rint = 0.034
Graphite monochromator	θmax = 27.5°, θmin = 2.4°
φ scans with κ at 0° and ω scans	h = −8→8
9229 measured reflections	k = −10→10
1910 independent reflections	l = −11→11

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.024	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.064	All H-atom parameters refined
S = 1.07	w = 1/[σ^2(Fo^2) + (0.023P)^2 + 0.3498P] where P = (Fo^2 + 2Fc^2)/3
1910 reflections	(Δ/σ)max = 0.001
162 parameters	Δρmax = 0.42 e Å^−3
0 restraints	Δρmin = −0.36 e Å^−3

Special details

Experimental. The same crystal was measured at three temperatures, 293 K, 150 K and 100 K. For each data set, intensities were measured with a Nonius KappaCCD diffractometer. The initial orientation matrix and cell parameters were obtained by indexing, integrating and refinement of spots on each image using DENZO (Otwinowski & Minor, 1997), and were used to calculate an optimal strategy for data collection. The final unit-cell parameters are obtained by reindexing the collected images using their kappa-geometry orientation matrices as a basis without interframe scaling refinement. Cell parameters were determined by SCALEPACK (Otwinowski & Minor, 1997) using the positions of measured reflections (with θ values varying from 2 to 28°). At 100 K the dataset was 99.7% complete out to 28° in two-theta; at 150 K the completeness was 99.8% out to 27.5° in two-theta, and at 293 K, the data were 99.7% complete out to 27.5° in two-theta.

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
P1	0.19666 (5)	0.16114 (5)	0.51466 (4)	0.00876 (10)
P2	0.26603 (5)	−0.05715 (5)	0.85369 (4)	0.00869 (10)
O3	0.30545 (16)	0.28997 (14)	0.41063 (12)	0.0127 (2)
O4	0.26058 (15)	−0.02988 (14)	1.02531 (11)	0.0120 (2)
O5	0.26545 (15)	−0.03272 (13)	0.48536 (12)	0.0111 (2)
O6	−0.04329 (16)	0.25157 (14)	0.49850 (12)	0.0127 (2)
O7	0.06601 (16)	−0.09877 (14)	0.81336 (12)	0.0125 (2)
O8	0.45972 (15)	−0.20064 (14)	0.81226 (12)	0.0129 (2)
N9	0.45904 (19)	0.20084 (17)	0.73163 (15)	0.0108 (2)
C10	0.2503 (2)	0.16564 (18)	0.72343 (16)	0.0092 (3)
C11	0.0894 (2)	0.33072 (19)	0.78710 (17)	0.0124 (3)
C12	0.2210 (3)	0.4251 (2)	0.85696 (19)	0.0181 (3)
C13	0.4122 (3)	0.3986 (2)	0.7477 (2)	0.0176 (3)
H11A	0.005 (3)	0.419 (2)	0.699 (2)	0.012 (4)*
H13A	0.382 (3)	0.474 (3)	0.641 (2)	0.021 (5)*
H11B	−0.005 (3)	0.288 (3)	0.868 (2)	0.019 (5)*
H12A	0.263 (3)	0.363 (3)	0.967 (2)	0.021 (5)*
H12B	0.151 (3)	0.550 (3)	0.853 (2)	0.024 (5)*
H13B	0.529 (3)	0.415 (3)	0.790 (2)	0.023 (5)*
H7	−0.037 (4)	−0.055 (4)	0.870 (3)	0.047 (7)*
H6	−0.105 (4)	0.178 (4)	0.496 (3)	0.051 (8)*
H3	0.396 (5)	0.247 (5)	0.330 (4)	0.085 (11)*
H9A	0.532 (3)	0.130 (3)	0.819 (2)	0.016 (4)*
H9B	0.542 (3)	0.167 (3)	0.643 (3)	0.024 (5)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
P1	0.00831 (18)	0.00905 (18)	0.00778 (17)	−0.00113 (13)	−0.00033 (12)	−0.00131 (12)
P2	0.00889 (18)	0.00918 (18)	0.00724 (17)	−0.00206 (13)	0.00077 (12)	−0.00118 (12)
O3	0.0140 (5)	0.0121 (5)	0.0105 (5)	−0.0033 (4)	0.0027 (4)	−0.0010 (4)
O4	0.0113 (5)	0.0161 (5)	0.0077 (5)	−0.0033 (4)	0.0004 (4)	−0.0021 (4)
O5	0.0102 (5)	0.0112 (5)	0.0117 (5)	−0.0019 (4)	0.0000 (4)	−0.0036 (4)
O6	0.0093 (5)	0.0124 (5)	0.0158 (5)	−0.0008 (4)	−0.0025 (4)	−0.0042 (4)
O7	0.0116 (5)	0.0156 (5)	0.0118 (5)	−0.0054 (4)	0.0017 (4)	−0.0049 (4)
O8	0.0118 (5)	0.0121 (5)	0.0112 (5)	0.0002 (4)	0.0019 (4)	−0.0007 (4)
N9	0.0099 (5)	0.0125 (6)	0.0103 (6)	−0.0038 (4)	−0.0008 (4)	−0.0015 (5)
C10	0.0080 (6)	0.0106 (6)	0.0090 (6)	−0.0026 (5)	0.0002 (5)	−0.0019 (5)
C11	0.0129 (7)	0.0107 (6)	0.0118 (6)	−0.0006 (5)	0.0010 (5)	−0.0033 (5)
C12	0.0213 (8)	0.0128 (7)	0.0199 (8)	−0.0013 (6)	−0.0028 (6)	−0.0077 (6)
C13	0.0193 (8)	0.0121 (7)	0.0235 (8)	−0.0073 (6)	−0.0036 (6)	−0.0025 (6)

Geometric parameters (Å, º)

P1—O5	1.5004 (10)	N9—C10	1.5249 (17)
P1—O3	1.5285 (10)	N9—H9A	0.91 (2)
P1—O6	1.5558 (10)	N9—H9B	0.93 (2)
P1—C10	1.8512 (14)	C10—C11	1.5627 (19)
P2—O8	1.5023 (10)	C11—C12	1.531 (2)
P2—O4	1.5148 (10)	C11—H11A	0.986 (18)
P2—O7	1.5589 (10)	C11—H11B	0.98 (2)
P2—C10	1.8416 (14)	C12—C13	1.516 (2)
O3—H3	0.93 (3)	C12—H12A	0.98 (2)
O6—H6	0.81 (3)	C12—H12B	0.93 (2)
O7—H7	0.84 (3)	C13—H13A	0.98 (2)
N9—C13	1.5045 (18)	C13—H13B	0.94 (2)
O5—P1—O3	115.35 (6)	C11—C10—P2	112.59 (9)
O5—P1—O6	112.28 (6)	N9—C10—P1	110.31 (9)
O3—P1—O6	108.47 (6)	C11—C10—P1	111.80 (9)
O5—P1—C10	110.47 (6)	P2—C10—P1	110.58 (7)
O3—P1—C10	104.99 (6)	C12—C11—C10	105.25 (11)
O6—P1—C10	104.49 (6)	C12—C11—H11A	109.1 (10)
O8—P2—O4	113.13 (6)	C10—C11—H11A	111.0 (11)
O8—P2—O7	111.05 (6)	C12—C11—H11B	112.1 (11)
O4—P2—O7	111.49 (6)	C10—C11—H11B	110.9 (11)
O8—P2—C10	109.56 (6)	H11A—C11—H11B	108.4 (15)
O4—P2—C10	107.31 (6)	C13—C12—C11	102.75 (12)
O7—P2—C10	103.80 (6)	C13—C12—H12A	109.6 (11)
P1—O3—H3	119 (2)	C11—C12—H12A	111.1 (12)
P1—O6—H6	113.0 (19)	C13—C12—H12B	111.0 (13)
P2—O7—H7	112.5 (18)	C11—C12—H12B	111.3 (12)
C13—N9—C10	107.14 (11)	H12A—C12—H12B	110.9 (17)
C13—N9—H9A	107.7 (12)	N9—C13—C12	101.85 (12)
C10—N9—H9A	111.6 (12)	N9—C13—H13A	107.8 (12)
C13—N9—H9B	115.4 (13)	C12—C13—H13A	112.5 (11)
C10—N9—H9B	109.6 (13)	N9—C13—H13B	109.4 (12)
H9A—N9—H9B	105.5 (17)	C12—C13—H13B	114.6 (12)
N9—C10—C11	103.78 (10)	H13A—C13—H13B	110.2 (17)
N9—C10—P2	107.47 (9)
C13—N9—C10—C11	−16.64 (14)	O6—P1—C10—N9	−143.89 (9)
C13—N9—C10—P2	−136.10 (10)	O5—P1—C10—C11	−149.91 (9)
C13—N9—C10—P1	103.26 (11)	O3—P1—C10—C11	85.12 (10)
O8—P2—C10—N9	−51.02 (10)	O6—P1—C10—C11	−28.95 (11)
O4—P2—C10—N9	72.16 (10)	O5—P1—C10—P2	−23.60 (9)
O7—P2—C10—N9	−169.69 (8)	O3—P1—C10—P2	−148.56 (7)
O8—P2—C10—C11	−164.69 (9)	O6—P1—C10—P2	97.37 (7)
O4—P2—C10—C11	−41.50 (11)	N9—C10—C11—C12	−10.82 (14)
O7—P2—C10—C11	76.64 (10)	P2—C10—C11—C12	105.08 (11)
O8—P2—C10—P1	69.44 (8)	P1—C10—C11—C12	−129.71 (10)
O4—P2—C10—P1	−167.38 (6)	C10—C11—C12—C13	33.90 (14)
O7—P2—C10—P1	−49.23 (8)	C10—N9—C13—C12	37.89 (14)
O5—P1—C10—N9	95.15 (9)	C11—C12—C13—N9	−43.79 (14)
O3—P1—C10—N9	−29.82 (10)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O8^i	0.93 (3)	1.52 (3)	2.4447 (14)	173 (3)
O6—H6···O5^ii	0.81 (3)	1.77 (3)	2.5754 (15)	171 (3)
O7—H7···O4^iii	0.84 (3)	1.70 (3)	2.5406 (14)	175 (3)
N9—H9A···O4^iv	0.91 (2)	1.88 (2)	2.7523 (16)	161.5 (17)
N9—H9B···O5^i	0.93 (2)	1.84 (2)	2.7395 (16)	162.0 (19)

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

(III) pyrrolidin-2,2-diylbis(phosphonic acid)

Crystal data

C4H11NO6P2	Z = 2
Mr = 231.08	F(000) = 240
Triclinic, P1	Dx = 1.827 Mg m^−3 Dm = 1.85 (2) Mg m^−3 Dm measured by flotation
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.7703 (2) Å	Cell parameters from all reflections
b = 7.8135 (2) Å	θ = 2.4–27.5°
c = 8.5263 (2) Å	µ = 0.52 mm^−1
α = 78.7105 (12)°	T = 293 K
β = 85.5530 (16)°	Plate, colourless
γ = 71.7958 (14)°	0.44 × 0.19 × 0.12 mm
V = 420.11 (2) Å^3

Data collection

Nonius Kappa CCD area detector diffractometer	1824 reflections with I > 2σ(I)
Radiation source: rotating anode	Rint = 0.033
Graphite monochromator	θmax = 27.5°, θmin = 2.4°
φ scans with κ at 0° and ω scans	h = −8→8
9911 measured reflections	k = −10→10
1921 independent reflections	l = −11→11

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.024	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.065	All H-atom parameters refined
S = 1.08	w = 1/[σ^2(Fo^2) + (0.0229P)^2 + 0.2908P] where P = (Fo^2 + 2Fc^2)/3
1921 reflections	(Δ/σ)max = 0.001
162 parameters	Δρmax = 0.40 e Å^−3
0 restraints	Δρmin = −0.33 e Å^−3

Special details

Experimental. The same crystal was measured at three temperatures, 293 K, 150 K and 100 K. For each data set, intensities were measured with a Nonius KappaCCD diffractometer. The initial orientation matrix and cell parameters were obtained by indexing, integrating and refinement of spots on each image using DENZO (Otwinowski & Minor, 1997), and were used to calculate an optimal strategy for data collection. The final unit-cell parameters are obtained by reindexing the collected images using their kappa-geometry orientation matrices as a basis without interframe scaling refinement. Cell parameters were determined by SCALEPACK (Otwinowski & Minor, 1997) using the positions of measured reflections (with θ values varying from 2 to 28°). At 100 K the dataset was 99.7% complete out to 28° in two-theta; at 150 K the completeness was 99.8% out to 27.5° in two-theta, and at 293 K, the data were 99.7% complete out to 27.5° in two-theta.

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
P1	0.19660 (5)	0.16050 (5)	0.51496 (4)	0.01549 (10)
P2	0.26546 (5)	−0.05611 (5)	0.85366 (4)	0.01546 (10)
O3	0.30427 (17)	0.28855 (15)	0.41073 (13)	0.0223 (2)
H3	0.397 (5)	0.244 (5)	0.332 (4)	0.105 (12)*
O4	0.26057 (16)	−0.02884 (15)	1.02497 (12)	0.0209 (2)
O5	0.26518 (15)	−0.03264 (14)	0.48567 (12)	0.0191 (2)
O6	−0.04250 (16)	0.25044 (15)	0.49981 (13)	0.0227 (2)
H6	−0.104 (4)	0.181 (4)	0.497 (3)	0.057 (8)*
O7	0.06655 (17)	−0.09761 (15)	0.81399 (13)	0.0220 (2)
H7	−0.042 (4)	−0.052 (4)	0.872 (3)	0.064 (8)*
O8	0.45858 (16)	−0.19934 (14)	0.81232 (13)	0.0231 (2)
N9	0.45868 (19)	0.19983 (17)	0.73142 (15)	0.0184 (2)
H9A	0.532 (3)	0.128 (3)	0.821 (2)	0.026 (5)*
H9B	0.540 (3)	0.167 (3)	0.642 (3)	0.032 (5)*
C10	0.2504 (2)	0.16550 (18)	0.72352 (16)	0.0152 (3)
C11	0.0909 (2)	0.3308 (2)	0.78708 (18)	0.0219 (3)
H11A	0.006 (3)	0.417 (3)	0.701 (2)	0.024 (4)*
H11B	−0.001 (3)	0.289 (3)	0.869 (3)	0.035 (5)*
C12	0.2222 (3)	0.4246 (2)	0.8559 (2)	0.0321 (4)
H12A	0.153 (3)	0.549 (3)	0.850 (3)	0.038 (6)*
H12B	0.261 (3)	0.366 (3)	0.966 (3)	0.039 (6)*
C13	0.4128 (3)	0.3965 (2)	0.7476 (2)	0.0314 (4)
H13A	0.383 (3)	0.471 (3)	0.639 (3)	0.037 (6)*
H13B	0.530 (4)	0.411 (3)	0.790 (3)	0.042 (6)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
P1	0.01479 (18)	0.01618 (18)	0.01367 (18)	−0.00214 (13)	−0.00064 (12)	−0.00251 (13)
P2	0.01612 (19)	0.01666 (18)	0.01263 (18)	−0.00439 (14)	0.00150 (12)	−0.00199 (13)
O3	0.0249 (6)	0.0211 (5)	0.0184 (5)	−0.0061 (4)	0.0046 (4)	−0.0015 (4)
O4	0.0196 (5)	0.0284 (6)	0.0133 (5)	−0.0057 (4)	0.0004 (4)	−0.0034 (4)
O5	0.0173 (5)	0.0196 (5)	0.0197 (5)	−0.0030 (4)	0.0003 (4)	−0.0064 (4)
O6	0.0158 (5)	0.0220 (5)	0.0287 (6)	−0.0012 (4)	−0.0047 (4)	−0.0067 (4)
O7	0.0209 (5)	0.0282 (6)	0.0207 (5)	−0.0110 (4)	0.0029 (4)	−0.0085 (4)
O8	0.0215 (5)	0.0213 (5)	0.0197 (5)	0.0005 (4)	0.0034 (4)	−0.0006 (4)
N9	0.0175 (6)	0.0214 (6)	0.0170 (6)	−0.0070 (5)	−0.0007 (5)	−0.0032 (5)
C10	0.0140 (6)	0.0166 (6)	0.0147 (6)	−0.0042 (5)	0.0006 (5)	−0.0029 (5)
C11	0.0217 (7)	0.0197 (7)	0.0212 (7)	−0.0007 (6)	0.0017 (6)	−0.0066 (6)
C12	0.0383 (10)	0.0223 (8)	0.0356 (9)	−0.0028 (7)	−0.0058 (8)	−0.0141 (7)
C13	0.0350 (9)	0.0213 (8)	0.0417 (10)	−0.0135 (7)	−0.0060 (8)	−0.0042 (7)

Geometric parameters (Å, º)

P1—O5	1.4990 (10)	N9—C10	1.5239 (17)
P1—O3	1.5262 (11)	N9—H9A	0.93 (2)
P1—O6	1.5547 (11)	N9—H9B	0.94 (2)
P1—C10	1.8529 (14)	C10—C11	1.5619 (19)
P2—O8	1.5016 (11)	C11—C12	1.526 (2)
P2—O4	1.5133 (10)	C11—H11A	0.975 (19)
P2—O7	1.5554 (11)	C11—H11B	0.98 (2)
P2—C10	1.8426 (14)	C12—C13	1.511 (3)
O3—H3	0.92 (4)	C12—H12A	0.93 (2)
O6—H6	0.78 (3)	C12—H12B	0.98 (2)
O7—H7	0.87 (3)	C13—H13A	0.99 (2)
N9—C13	1.501 (2)	C13—H13B	0.94 (2)
O5—P1—O3	115.38 (6)	C11—C10—P2	112.72 (9)
O5—P1—O6	112.30 (6)	N9—C10—P1	110.35 (9)
O3—P1—O6	108.46 (6)	C11—C10—P1	111.80 (9)
O5—P1—C10	110.45 (6)	P2—C10—P1	110.54 (7)
O3—P1—C10	105.08 (6)	C12—C11—C10	105.35 (12)
O6—P1—C10	104.37 (6)	C12—C11—H11A	109.4 (11)
O8—P2—O4	112.88 (6)	C10—C11—H11A	111.4 (11)
O8—P2—O7	111.12 (6)	C12—C11—H11B	111.2 (12)
O4—P2—O7	111.52 (6)	C10—C11—H11B	110.8 (12)
O8—P2—C10	109.48 (6)	H11A—C11—H11B	108.6 (16)
O4—P2—C10	107.38 (6)	C13—C12—C11	102.93 (13)
O7—P2—C10	104.00 (6)	C13—C12—H12A	110.5 (13)
P1—O3—H3	118 (2)	C11—C12—H12A	111.2 (13)
P1—O6—H6	114.0 (19)	C13—C12—H12B	110.3 (13)
P2—O7—H7	113.7 (18)	C11—C12—H12B	111.3 (13)
C13—N9—C10	107.15 (11)	H12A—C12—H12B	110.3 (18)
C13—N9—H9A	107.7 (12)	N9—C13—C12	102.05 (13)
C10—N9—H9A	111.1 (12)	N9—C13—H13A	106.8 (12)
C13—N9—H9B	115.0 (12)	C12—C13—H13A	112.6 (12)
C10—N9—H9B	108.9 (12)	N9—C13—H13B	109.1 (14)
H9A—N9—H9B	107.1 (17)	C12—C13—H13B	115.1 (14)
N9—C10—C11	103.66 (11)	H13A—C13—H13B	110.5 (18)
N9—C10—P2	107.48 (9)
C13—N9—C10—C11	−16.50 (14)	O6—P1—C10—N9	−144.15 (9)
C13—N9—C10—P2	−136.05 (11)	O5—P1—C10—C11	−150.24 (10)
C13—N9—C10—P1	103.35 (12)	O3—P1—C10—C11	84.72 (11)
O8—P2—C10—N9	−50.80 (10)	O6—P1—C10—C11	−29.34 (11)
O4—P2—C10—N9	72.08 (10)	O5—P1—C10—P2	−23.80 (9)
O7—P2—C10—N9	−169.62 (9)	O3—P1—C10—P2	−148.85 (7)
O8—P2—C10—C11	−164.40 (10)	O6—P1—C10—P2	97.10 (8)
O4—P2—C10—C11	−41.51 (11)	N9—C10—C11—C12	−10.66 (15)
O7—P2—C10—C11	76.79 (11)	P2—C10—C11—C12	105.24 (13)
O8—P2—C10—P1	69.68 (8)	P1—C10—C11—C12	−129.52 (12)
O4—P2—C10—P1	−167.43 (6)	C10—C11—C12—C13	33.57 (16)
O7—P2—C10—P1	−49.13 (8)	C10—N9—C13—C12	37.56 (16)
O5—P1—C10—N9	94.95 (10)	C11—C12—C13—N9	−43.43 (16)
O3—P1—C10—N9	−30.09 (10)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O8^i	0.92 (4)	1.54 (4)	2.4550 (15)	171 (4)
O6—H6···O5^ii	0.78 (3)	1.80 (3)	2.5838 (16)	172 (3)
O7—H7···O4^iii	0.87 (3)	1.67 (3)	2.5414 (15)	176 (3)
N9—H9A···O4^iv	0.93 (2)	1.87 (2)	2.7661 (16)	160.6 (17)
N9—H9B···O5^i	0.94 (2)	1.84 (2)	2.7409 (16)	160.8 (19)

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