[Hydro­xy(4-pyridyl)­methyl]­phospho­nic acid monohydrate

The title compound, C₆H₈O₄NP·H₂O, contains one phosphon­ate group and one pyridyl ring connected by a CH(OH) group. The pyridyl N atom and one of the three phospho­nate O atoms are protonated. Extensive hydrogen-bonding interactions, as well as π–π-stacking interactions, are found between the mol­ecules, thus generating a three-dimensional supramolecular network structure.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.043
• wR factor = 0.103
• Data-to-parameter ratio = 12.1

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

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Computing details

Data collection: SMART (Bruker, 1997); cell refinement: SMART; data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXTL (Bruker, 1997); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

[Hydroxy(4-pyridyl)methyl]phosphonic acid monohydrate

Crystal data

C6H8NO4P·H2O	F(000) = 432
Mr = 207.12	Dx = 1.671 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 1197 reflections
a = 6.486 (1) Å	θ = 2.6–23.9°
b = 15.464 (3) Å	µ = 0.32 mm^−1
c = 8.457 (2) Å	T = 293 K
β = 103.91 (1)°	Column, colorless
V = 823.3 (3) Å^3	0.30 × 0.25 × 0.10 mm
Z = 4

Data collection

Bruker SMART APEX CCD diffractometer	1613 independent reflections
Radiation source: fine-focus sealed tube	1189 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.056
φ and ω scans	θmax = 26.0°, θmin = 2.6°
Absorption correction: empirical (using intensity measurements) (SADABS; Sheldrick, 1997)	h = −8→7
Tmin = 0.906, Tmax = 0.966	k = 0→19
4405 measured reflections	l = 0→10

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)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.103	H atoms treated by a mixture of independent and constrained refinement
S = 0.94	w = 1/[σ^2(Fo^2) + (0.0566P)^2] where P = (Fo^2 + 2Fc^2)/3
1613 reflections	(Δ/σ)max < 0.001
133 parameters	Δρmax = 0.50 e Å^−3
0 restraints	Δρmin = −0.31 e Å^−3

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. The structure was solved by direct methods and successive difference Fourier syntheses.

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	0.12248 (10)	0.76824 (4)	0.54576 (8)	0.0230 (2)
O1	0.3073 (3)	0.82852 (12)	0.5804 (2)	0.0306 (5)
O2	−0.0848 (3)	0.80124 (12)	0.4462 (2)	0.0318 (5)
O3	0.0825 (3)	0.73396 (13)	0.7110 (2)	0.0325 (5)
H3	0.183 (5)	0.727 (2)	0.780 (4)	0.045*
O4	0.0128 (3)	0.61959 (13)	0.3815 (2)	0.0388 (5)
H4	−0.064 (5)	0.644 (2)	0.282 (4)	0.054*
O1W	0.8688 (3)	0.41828 (14)	0.9975 (3)	0.0370 (5)
H1WA	0.772 (5)	0.377 (2)	1.008 (4)	0.052*
H1WB	0.946 (5)	0.388 (2)	0.969 (4)	0.052*
N1	0.6554 (3)	0.52927 (15)	0.7759 (3)	0.0305 (6)
H1N	0.744 (4)	0.4937 (18)	0.851 (4)	0.043*
C1	0.4521 (4)	0.50419 (18)	0.7443 (3)	0.0335 (7)
H1C	0.4137	0.4564	0.7977	0.040*
C2	0.3014 (4)	0.54843 (17)	0.6345 (3)	0.0306 (7)
H2C	0.1604	0.5306	0.6123	0.037*
C3	0.3576 (4)	0.61976 (17)	0.5557 (3)	0.0230 (6)
C4	0.5703 (4)	0.64302 (17)	0.5909 (3)	0.0287 (6)
H4C	0.6139	0.6902	0.5388	0.034*
C5	0.7151 (4)	0.59667 (18)	0.7019 (3)	0.0312 (7)
H5C	0.8575	0.6126	0.7259	0.037*
C6	0.1915 (4)	0.67209 (17)	0.4403 (3)	0.0261 (6)
H6C	0.2483	0.6908	0.3485	0.031*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
P1	0.0188 (4)	0.0252 (4)	0.0222 (4)	0.0006 (3)	−0.0003 (3)	−0.0001 (3)
O1	0.0259 (10)	0.0306 (11)	0.0322 (11)	−0.0063 (8)	0.0011 (8)	−0.0002 (8)
O2	0.0221 (10)	0.0379 (11)	0.0305 (10)	0.0079 (8)	−0.0033 (8)	−0.0025 (9)
O3	0.0243 (10)	0.0465 (13)	0.0242 (10)	−0.0024 (9)	0.0010 (8)	0.0045 (9)
O4	0.0337 (12)	0.0334 (11)	0.0391 (12)	−0.0068 (9)	−0.0113 (9)	0.0008 (9)
O1W	0.0262 (11)	0.0358 (13)	0.0508 (13)	0.0038 (9)	0.0125 (10)	0.0118 (10)
N1	0.0257 (13)	0.0316 (14)	0.0295 (12)	0.0070 (10)	−0.0024 (10)	0.0000 (11)
C1	0.0366 (17)	0.0263 (16)	0.0372 (16)	−0.0001 (13)	0.0078 (13)	0.0031 (13)
C2	0.0233 (14)	0.0294 (16)	0.0365 (15)	0.0003 (12)	0.0021 (12)	0.0000 (13)
C3	0.0223 (13)	0.0233 (14)	0.0223 (13)	0.0036 (11)	0.0032 (10)	−0.0053 (11)
C4	0.0252 (14)	0.0313 (16)	0.0300 (15)	−0.0011 (12)	0.0073 (12)	0.0023 (12)
C5	0.0215 (14)	0.0357 (17)	0.0348 (16)	0.0008 (12)	0.0040 (12)	−0.0012 (13)
C6	0.0229 (14)	0.0262 (14)	0.0267 (14)	−0.0005 (11)	0.0010 (11)	−0.0006 (11)

Geometric parameters (Å, º)

P1—O1	1.4910 (18)	N1—H1N	0.93 (3)
P1—O2	1.4938 (17)	C1—C2	1.360 (4)
P1—O3	1.5736 (19)	C1—H1C	0.9300
P1—C6	1.843 (3)	C2—C3	1.382 (4)
O3—H3	0.77 (3)	C2—H2C	0.9300
O4—C6	1.404 (3)	C3—C4	1.387 (3)
O4—H4	0.95 (3)	C3—C6	1.504 (3)
O1W—H1WA	0.92 (3)	C4—C5	1.361 (3)
O1W—H1WB	0.77 (3)	C4—H4C	0.9300
N1—C5	1.321 (3)	C5—H5C	0.9300
N1—C1	1.339 (3)	C6—H6C	0.9800
O1—P1—O2	117.98 (11)	C3—C2—H2C	120.0
O1—P1—O3	109.43 (10)	C2—C3—C4	117.9 (2)
O2—P1—O3	107.30 (11)	C2—C3—C6	120.8 (2)
O1—P1—C6	108.79 (11)	C4—C3—C6	121.3 (2)
O2—P1—C6	107.04 (11)	C5—C4—C3	119.8 (3)
O3—P1—C6	105.61 (12)	C5—C4—H4C	120.1
P1—O3—H3	115 (2)	C3—C4—H4C	120.1
C6—O4—H4	107.2 (19)	N1—C5—C4	120.7 (2)
H1WA—O1W—H1WB	97 (3)	N1—C5—H5C	119.6
C5—N1—C1	121.4 (2)	C4—C5—H5C	119.6
C5—N1—H1N	126.1 (18)	O4—C6—C3	108.7 (2)
C1—N1—H1N	112.5 (18)	O4—C6—P1	111.21 (18)
N1—C1—C2	120.2 (3)	C3—C6—P1	109.83 (17)
N1—C1—H1C	119.9	O4—C6—H6C	109.0
C2—C1—H1C	119.9	C3—C6—H6C	109.0
C1—C2—C3	120.1 (3)	P1—C6—H6C	109.0
C1—C2—H2C	120.0
C5—N1—C1—C2	−0.2 (4)	C4—C3—C6—O4	158.5 (2)
N1—C1—C2—C3	−0.4 (4)	C2—C3—C6—P1	98.1 (3)
C1—C2—C3—C4	1.0 (4)	C4—C3—C6—P1	−79.6 (3)
C1—C2—C3—C6	−176.9 (2)	O1—P1—C6—O4	−170.53 (17)
C2—C3—C4—C5	−1.0 (4)	O2—P1—C6—O4	−42.0 (2)
C6—C3—C4—C5	176.8 (2)	O3—P1—C6—O4	72.09 (19)
C1—N1—C5—C4	0.2 (4)	O1—P1—C6—C3	69.2 (2)
C3—C4—C5—N1	0.4 (4)	O2—P1—C6—C3	−162.35 (17)
C2—C3—C6—O4	−23.7 (3)	O3—P1—C6—C3	−48.2 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O2^i	0.77 (3)	1.85 (3)	2.617 (2)	174 (3)
O4—H4···O1^ii	0.95 (3)	1.76 (3)	2.697 (3)	169 (3)
O1W—H1WA···O2^iii	0.92 (3)	1.79 (3)	2.705 (3)	173 (3)
O1W—H1WB···O1^iv	0.77 (3)	1.97 (3)	2.727 (3)	167 (4)
N1—H1N···O1W	0.93 (3)	1.75 (3)	2.669 (3)	170 (3)

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