4,4'-Methyl­enediantipyrine monohydrate

In the crystal structure of the title compound, C₂₃H₂₄N₄O₂·H₂O, the 4,4'-methyl­enedianti­pyrine mol­ecules are linked via hydrogen bonds through water mol­ecules to form centrosymmetric dimers.

Key indicators

• Single-crystal X-ray study
• T = 203 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.047
• wR factor = 0.130
• Data-to-parameter ratio = 13.1

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

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S1. Comment

4,4'-Methylenediantipyrine reacts with titanium(IV) in a strongly acid medium to form a complex having an absorption maximum at around 285 nm (Minin, 1955). This reaction has widely been used for selective photometric determination of titanium(IV). We report here the structure and hydrogen-bonding behavior of the title compound, (I). 4,4-Methylenediantipyrine crystallized from acetone as the monohydrate in the space group P2₁/c. The molecular structure is shown in Fig. 1.

The structure is dominated by the angle of the bridging C atom C8—C12—C13 between the two pyrazolone moities. There is no conjugation between the pyrazolone moieties and the phenyl rings. In the molecule, the two phenyl rings and the two pyrazolone rings are oriented with respect to each other at 55.6 and 54.0°. But the N2—C1 and N4—C18 bonds are slightly shorter than the accepted N—C single-bond distance of 1.47 (1) Å (Allen et al., 1987). This is in a good agreement with the determined structures of phenanzone (Singh & Vijayan, 1973) and other metal–pyrazolone complexes (Vijayan & Viswamitra, 1968). All the lengths in the moieties lie between the corresponding single- and double-bond distances. However, the C9—C10 distance deviates from the usual length of 1.54 (1) Å (Allen et al., 1987) of a C—C single bond. This might be partly due to the sp² hybridization state of atom C9. Distances and angles of special interest are given in Table 1.

Another striking feature of this compound is the orientation of the two pyrazolone moieties. The differences between the molecular dimensions of free 4,4'-methylenediantipyrine monohydrate determined from the present study and the structure observed in the titanium(IV)-antipyrine complexes (Yuchi, 1991) are significant. As a consequence of the confirmation of the bridging atom C12, the carboxyl groups of the pyrazolone moieties in the free 4,4'-methylenediantipyrine monohydrate have contrary orientations. In contrast, 4,4'-methylenediantipyrine acts as a bidentate ligand to form eight-membered chelate rings with tin(IV) tetrachloride.

Each pyrazolone moiety in the title compound is nearly planar, but the C atoms of the phenyl groups are not coplanar with the pyrazolone moieties (Table 1). The dihedral angle between the pyrazolone moieties is 110.9 (2)°. The crystal lattice is held together by hydrogen-bond interactions building dimeric units containing 16-membered rings (Fig. 2). The water molecule is linked to the carboxyl groups via hydrogen bonds (Table 2).

S2. Experimental

4,4'-Methylenediantipyrine monohydrate was heated in acetone until most of the solid was dissolved. Crystals suitable for X-ray diffraction analysis were obtained by slowly cooling of the solution containing a few drops of heptane.

Computing details

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Siemens, 1996); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Figures

	Fig. 1. The molecular structure of (I), showing 50% probability displacement ellipsiods.
	Fig. 2. The dimeric units in the title compound, showing the hydrogen bonding between the water molecules and the carboxyl groups of the pyrazolone moities.

(I)

Crystal data

C23H24N4O2·H2O	F(000) = 864
Mr = 406.48	Dx = 1.271 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 11.937 (3) Å	Cell parameters from 83 reflections
b = 14.740 (4) Å	θ = 3.2–19.7°
c = 12.085 (3) Å	µ = 0.09 mm^−1
β = 92.436 (5)°	T = 203 K
V = 2124.4 (10) Å^3	Plates, colourless
Z = 4	0.4 × 0.3 × 0.1 mm

Data collection

Bruker CCD 1000 diffractometer	3704 independent reflections
Radiation source: fine-focus sealed tube	3017 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.037
ω scans	θmax = 25.0°, θmin = 2.7°
Absorption correction: empirical (using intensity measurements) (Blessing, 1995)	h = −12→14
Tmin = 0.970, Tmax = 0.991	k = −17→17
12780 measured reflections	l = −14→12

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)] = 0.047	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.130	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ^2(Fo^2) + (0.0661P)^2 + 0.63P] where P = (Fo^2 + 2Fc^2)/3
3704 reflections	(Δ/σ)max = 0.001
282 parameters	Δρmax = 0.19 e Å^−3
0 restraints	Δρmin = −0.18 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. 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
O1	0.70112 (12)	0.61762 (9)	0.36296 (11)	0.0475 (4)
C1	0.83082 (13)	0.36051 (11)	0.88481 (14)	0.0314 (4)
N1	0.70776 (12)	0.40512 (10)	0.72856 (13)	0.0393 (4)
O2	0.96615 (10)	0.50286 (9)	0.78919 (11)	0.0445 (3)
N2	0.79887 (12)	0.42539 (9)	0.80164 (12)	0.0354 (4)
C2	0.80865 (15)	0.26890 (12)	0.86868 (15)	0.0377 (4)
H2A	0.7725	0.2488	0.8026	0.045*
H26	0.786 (3)	0.525 (2)	0.310 (3)	0.105 (10)*
H27	0.892 (3)	0.482 (2)	0.262 (2)	0.097 (10)*
N3	0.74879 (13)	0.79490 (9)	0.54638 (12)	0.0373 (4)
C3	0.84015 (17)	0.20756 (12)	0.95055 (17)	0.0450 (5)
H3A	0.8250	0.1455	0.9401	0.054*
O3	0.81822 (14)	0.46905 (10)	0.28413 (14)	0.0571 (4)
N4	0.70539 (12)	0.75850 (9)	0.44667 (12)	0.0357 (4)
C4	0.89373 (17)	0.23663 (13)	1.04763 (17)	0.0481 (5)
H4A	0.9146	0.1946	1.1032	0.058*
C5	0.91646 (17)	0.32759 (13)	1.06275 (16)	0.0458 (5)
H5A	0.9536	0.3473	1.1286	0.055*
C6	0.88513 (15)	0.38982 (11)	0.98195 (15)	0.0377 (4)
H6A	0.9005	0.4518	0.9927	0.045*
C7	0.87284 (14)	0.48218 (11)	0.74848 (14)	0.0315 (4)
C8	0.81876 (14)	0.50457 (11)	0.64333 (14)	0.0323 (4)
C9	0.72036 (14)	0.45879 (12)	0.63677 (15)	0.0372 (4)
C10	0.63024 (18)	0.45903 (17)	0.54749 (19)	0.0580 (6)
H10A	0.5648	0.4902	0.5734	0.087*
H10B	0.6105	0.3970	0.5281	0.087*
H10C	0.6569	0.4900	0.4828	0.087*
C11	0.59944 (17)	0.39928 (17)	0.7809 (2)	0.0602 (6)
H11A	0.5412	0.3850	0.7252	0.090*
H11B	0.5828	0.4569	0.8152	0.090*
H11C	0.6026	0.3521	0.8368	0.090*
C12	0.87121 (14)	0.56322 (12)	0.55738 (15)	0.0355 (4)
H12A	0.9487	0.5763	0.5823	0.043*
H12B	0.8739	0.5285	0.4884	0.043*
C13	0.81259 (14)	0.65181 (11)	0.53251 (14)	0.0317 (4)
C14	0.82012 (14)	0.73021 (11)	0.59169 (14)	0.0343 (4)
C15	0.73695 (14)	0.66817 (11)	0.43858 (14)	0.0343 (4)
C16	0.89230 (17)	0.75129 (14)	0.69192 (17)	0.0479 (5)
H16A	0.9238	0.6955	0.7224	0.072*
H16B	0.8476	0.7806	0.7468	0.072*
H16C	0.9525	0.7915	0.6719	0.072*
C17	0.7821 (2)	0.89059 (13)	0.5405 (2)	0.0649 (7)
H17A	0.8062	0.9116	0.6138	0.097*
H17B	0.7188	0.9266	0.5131	0.097*
H17C	0.8433	0.8968	0.4908	0.097*
C18	0.60641 (14)	0.79685 (11)	0.39530 (15)	0.0366 (4)
C19	0.59687 (19)	0.80375 (17)	0.28303 (18)	0.0590 (6)
H19A	0.6553	0.7837	0.2394	0.071*
C20	0.5007 (2)	0.84037 (19)	0.2336 (2)	0.0757 (8)
H20A	0.4944	0.8451	0.1560	0.091*
C21	0.4151 (2)	0.86964 (16)	0.2948 (3)	0.0729 (8)
H21A	0.3497	0.8941	0.2605	0.087*
C22	0.4261 (2)	0.8627 (3)	0.4063 (3)	0.1027 (12)
H22A	0.3676	0.8830	0.4498	0.123*
C23	0.5213 (2)	0.8264 (2)	0.4576 (2)	0.0856 (9)
H23A	0.5274	0.8220	0.5353	0.103*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0611 (9)	0.0396 (7)	0.0405 (8)	0.0122 (6)	−0.0125 (6)	−0.0073 (6)
C1	0.0288 (8)	0.0305 (8)	0.0347 (9)	0.0002 (6)	−0.0004 (7)	0.0033 (7)
N1	0.0279 (8)	0.0447 (8)	0.0445 (9)	−0.0063 (6)	−0.0085 (6)	0.0096 (7)
O2	0.0381 (7)	0.0479 (7)	0.0464 (8)	−0.0139 (6)	−0.0113 (6)	0.0077 (6)
N2	0.0313 (8)	0.0359 (8)	0.0384 (9)	−0.0048 (6)	−0.0077 (6)	0.0070 (6)
C2	0.0394 (10)	0.0357 (9)	0.0377 (10)	−0.0077 (7)	−0.0015 (8)	−0.0024 (8)
N3	0.0418 (8)	0.0322 (7)	0.0375 (9)	0.0033 (6)	−0.0006 (7)	−0.0025 (6)
C3	0.0537 (12)	0.0288 (9)	0.0523 (12)	−0.0051 (8)	0.0020 (9)	0.0042 (8)
O3	0.0508 (9)	0.0428 (8)	0.0784 (11)	−0.0049 (7)	0.0103 (8)	−0.0080 (8)
N4	0.0399 (8)	0.0340 (7)	0.0330 (8)	0.0082 (6)	−0.0018 (6)	0.0012 (6)
C4	0.0583 (12)	0.0406 (10)	0.0448 (12)	0.0033 (9)	−0.0048 (9)	0.0131 (9)
C5	0.0551 (12)	0.0451 (11)	0.0361 (10)	−0.0010 (9)	−0.0113 (9)	0.0002 (8)
C6	0.0422 (10)	0.0301 (8)	0.0403 (10)	0.0005 (7)	−0.0053 (8)	−0.0017 (7)
C7	0.0305 (9)	0.0274 (8)	0.0361 (10)	−0.0016 (6)	−0.0033 (7)	0.0008 (7)
C8	0.0318 (9)	0.0290 (8)	0.0358 (10)	0.0046 (7)	−0.0019 (7)	0.0020 (7)
C9	0.0321 (9)	0.0387 (9)	0.0402 (10)	0.0031 (7)	−0.0070 (7)	0.0050 (8)
C10	0.0400 (11)	0.0754 (15)	0.0568 (14)	−0.0049 (10)	−0.0184 (10)	0.0157 (11)
C11	0.0328 (11)	0.0800 (16)	0.0675 (15)	−0.0063 (10)	−0.0016 (10)	0.0243 (12)
C12	0.0329 (9)	0.0376 (9)	0.0358 (10)	0.0063 (7)	−0.0001 (7)	0.0040 (7)
C13	0.0304 (9)	0.0344 (9)	0.0306 (9)	0.0022 (7)	0.0048 (7)	0.0043 (7)
C14	0.0316 (9)	0.0382 (9)	0.0331 (10)	−0.0005 (7)	0.0034 (7)	0.0043 (7)
C15	0.0365 (9)	0.0331 (9)	0.0335 (10)	0.0060 (7)	0.0031 (7)	0.0015 (7)
C16	0.0466 (11)	0.0521 (11)	0.0443 (12)	−0.0015 (9)	−0.0061 (9)	−0.0039 (9)
C17	0.0802 (16)	0.0326 (10)	0.0801 (17)	0.0009 (10)	−0.0182 (13)	−0.0016 (10)
C18	0.0336 (9)	0.0321 (9)	0.0441 (11)	0.0054 (7)	0.0017 (8)	0.0064 (8)
C19	0.0551 (13)	0.0754 (15)	0.0463 (13)	0.0222 (11)	−0.0005 (10)	0.0074 (11)
C20	0.0814 (18)	0.0794 (17)	0.0635 (16)	0.0205 (14)	−0.0292 (14)	0.0071 (13)
C21	0.0485 (14)	0.0529 (13)	0.115 (2)	0.0122 (11)	−0.0278 (14)	0.0032 (14)
C22	0.0581 (17)	0.146 (3)	0.106 (3)	0.0536 (19)	0.0194 (16)	0.025 (2)
C23	0.0655 (16)	0.130 (2)	0.0626 (16)	0.0497 (16)	0.0213 (13)	0.0251 (16)

Geometric parameters (Å, º)

O1—C15	1.241 (2)	C10—H10A	0.9700
C1—C6	1.386 (2)	C10—H10B	0.9700
C1—C2	1.388 (2)	C10—H10C	0.9700
C1—N2	1.427 (2)	C11—H11A	0.9700
N1—C9	1.376 (2)	C11—H11B	0.9700
N1—N2	1.404 (2)	C11—H11C	0.9700
N1—C11	1.466 (3)	C12—C13	1.506 (2)
O2—C7	1.237 (2)	C12—H12A	0.9800
N2—C7	1.393 (2)	C12—H12B	0.9800
C2—C3	1.381 (3)	C13—C14	1.360 (2)
C2—H2A	0.9400	C13—C15	1.440 (2)
N3—C14	1.376 (2)	C14—C16	1.489 (3)
N3—N4	1.398 (2)	C16—H16A	0.9700
N3—C17	1.468 (2)	C16—H16B	0.9700
C3—C4	1.380 (3)	C16—H16C	0.9700
C3—H3A	0.9400	C17—H17A	0.9700
O3—H26	0.96 (3)	C17—H17B	0.9700
O3—H27	0.96 (3)	C17—H17C	0.9700
N4—C15	1.388 (2)	C18—C19	1.361 (3)
N4—C18	1.428 (2)	C18—C23	1.362 (3)
C4—C5	1.379 (3)	C19—C20	1.381 (3)
C4—H4A	0.9400	C19—H19A	0.9400
C5—C6	1.380 (3)	C20—C21	1.357 (4)
C5—H5A	0.9400	C20—H20A	0.9400
C6—H6A	0.9400	C21—C22	1.353 (4)
C7—C8	1.439 (2)	C21—H21A	0.9400
C8—C9	1.354 (2)	C22—C23	1.379 (4)
C8—C12	1.508 (2)	C22—H22A	0.9400
C9—C10	1.491 (3)	C23—H23A	0.9400
C6—C1—C2	120.11 (16)	N1—C11—H11C	109.5
C6—C1—N2	119.27 (15)	H11A—C11—H11C	109.5
C2—C1—N2	120.61 (15)	H11B—C11—H11C	109.5
C9—N1—N2	106.05 (13)	C13—C12—C8	115.57 (14)
C9—N1—C11	120.67 (15)	C13—C12—H12A	108.4
N2—N1—C11	114.54 (16)	C8—C12—H12A	108.4
C7—N2—N1	109.09 (13)	C13—C12—H12B	108.4
C7—N2—C1	124.86 (14)	C8—C12—H12B	108.4
N1—N2—C1	118.49 (13)	H12A—C12—H12B	107.4
C3—C2—C1	119.47 (17)	C14—C13—C15	107.30 (15)
C3—C2—H2A	120.3	C14—C13—C12	127.75 (16)
C1—C2—H2A	120.3	C15—C13—C12	124.95 (15)
C14—N3—N4	106.09 (13)	C13—C14—N3	110.71 (16)
C14—N3—C17	121.37 (16)	C13—C14—C16	128.91 (16)
N4—N3—C17	114.74 (15)	N3—C14—C16	120.39 (16)
C4—C3—C2	120.53 (17)	O1—C15—N4	122.80 (16)
C4—C3—H3A	119.7	O1—C15—C13	131.65 (16)
C2—C3—H3A	119.7	N4—C15—C13	105.54 (15)
H26—O3—H27	109 (3)	C14—C16—H16A	109.5
C15—N4—N3	109.70 (13)	C14—C16—H16B	109.5
C15—N4—C18	124.83 (15)	H16A—C16—H16B	109.5
N3—N4—C18	119.48 (14)	C14—C16—H16C	109.5
C5—C4—C3	119.74 (17)	H16A—C16—H16C	109.5
C5—C4—H4A	120.1	H16B—C16—H16C	109.5
C3—C4—H4A	120.1	N3—C17—H17A	109.5
C4—C5—C6	120.46 (18)	N3—C17—H17B	109.5
C4—C5—H5A	119.8	H17A—C17—H17B	109.5
C6—C5—H5A	119.8	N3—C17—H17C	109.5
C5—C6—C1	119.68 (16)	H17A—C17—H17C	109.5
C5—C6—H6A	120.2	H17B—C17—H17C	109.5
C1—C6—H6A	120.2	C19—C18—C23	119.7 (2)
O2—C7—N2	122.85 (16)	C19—C18—N4	119.73 (17)
O2—C7—C8	131.11 (16)	C23—C18—N4	120.62 (19)
N2—C7—C8	106.01 (14)	C18—C19—C20	119.6 (2)
C9—C8—C7	107.03 (15)	C18—C19—H19A	120.2
C9—C8—C12	129.05 (16)	C20—C19—H19A	120.2
C7—C8—C12	123.79 (15)	C21—C20—C19	121.3 (3)
C8—C9—N1	111.33 (15)	C21—C20—H20A	119.3
C8—C9—C10	129.69 (17)	C19—C20—H20A	119.3
N1—C9—C10	118.99 (16)	C22—C21—C20	118.4 (2)
C9—C10—H10A	109.5	C22—C21—H21A	120.8
C9—C10—H10B	109.5	C20—C21—H21A	120.8
H10A—C10—H10B	109.5	C21—C22—C23	121.4 (3)
C9—C10—H10C	109.5	C21—C22—H22A	119.3
H10A—C10—H10C	109.5	C23—C22—H22A	119.3
H10B—C10—H10C	109.5	C18—C23—C22	119.7 (3)
N1—C11—H11A	109.5	C18—C23—H23A	120.1
N1—C11—H11B	109.5	C22—C23—H23A	120.1
H11A—C11—H11B	109.5
C9—N1—N2—C7	−7.34 (19)	N2—N1—C9—C10	−174.48 (17)
C11—N1—N2—C7	−142.96 (16)	C11—N1—C9—C10	−42.2 (3)
C9—N1—N2—C1	−158.51 (15)	C9—C8—C12—C13	69.4 (2)
C11—N1—N2—C1	65.9 (2)	C7—C8—C12—C13	−115.47 (18)
C6—C1—N2—C7	59.9 (2)	C8—C12—C13—C14	80.4 (2)
C2—C1—N2—C7	−119.66 (18)	C8—C12—C13—C15	−99.9 (2)
C6—C1—N2—N1	−153.84 (16)	C15—C13—C14—N3	3.87 (19)
C2—C1—N2—N1	26.6 (2)	C12—C13—C14—N3	−176.36 (16)
C6—C1—C2—C3	0.6 (3)	C15—C13—C14—C16	−175.83 (17)
N2—C1—C2—C3	−179.83 (16)	C12—C13—C14—C16	3.9 (3)
C1—C2—C3—C4	−0.3 (3)	N4—N3—C14—C13	−7.51 (19)
C14—N3—N4—C15	8.37 (18)	C17—N3—C14—C13	−140.82 (19)
C17—N3—N4—C15	145.20 (17)	N4—N3—C14—C16	172.22 (15)
C14—N3—N4—C18	162.43 (15)	C17—N3—C14—C16	38.9 (3)
C17—N3—N4—C18	−60.7 (2)	N3—N4—C15—O1	173.24 (16)
C2—C3—C4—C5	−0.3 (3)	C18—N4—C15—O1	20.9 (3)
C3—C4—C5—C6	0.6 (3)	N3—N4—C15—C13	−6.04 (18)
C4—C5—C6—C1	−0.2 (3)	C18—N4—C15—C13	−158.40 (16)
C2—C1—C6—C5	−0.4 (3)	C14—C13—C15—O1	−177.80 (19)
N2—C1—C6—C5	−179.91 (17)	C12—C13—C15—O1	2.4 (3)
N1—N2—C7—O2	−171.97 (16)	C14—C13—C15—N4	1.38 (18)
C1—N2—C7—O2	−23.1 (3)	C12—C13—C15—N4	−178.40 (15)
N1—N2—C7—C8	6.00 (18)	C15—N4—C18—C19	−67.7 (3)
C1—N2—C7—C8	154.90 (15)	N3—N4—C18—C19	142.39 (19)
O2—C7—C8—C9	175.38 (18)	C15—N4—C18—C23	112.1 (3)
N2—C7—C8—C9	−2.35 (18)	N3—N4—C18—C23	−37.8 (3)
O2—C7—C8—C12	−0.6 (3)	C23—C18—C19—C20	−0.2 (4)
N2—C7—C8—C12	−178.37 (15)	N4—C18—C19—C20	179.6 (2)
C7—C8—C9—N1	−2.3 (2)	C18—C19—C20—C21	−0.1 (4)
C12—C8—C9—N1	173.48 (16)	C19—C20—C21—C22	0.4 (4)
C7—C8—C9—C10	178.2 (2)	C20—C21—C22—C23	−0.4 (5)
C12—C8—C9—C10	−6.1 (3)	C19—C18—C23—C22	0.2 (4)
N2—N1—C9—C8	5.9 (2)	N4—C18—C23—C22	−179.6 (3)
C11—N1—C9—C8	138.22 (19)	C21—C22—C23—C18	0.1 (6)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H26···O1	0.96 (3)	1.83 (3)	2.788 (2)	170 (3)
O3—H27···O2^i	0.96 (3)	1.84 (3)	2.789 (2)	175 (3)

Symmetry code: (i) −x+2, −y+1, −z+1.