Crystal structure of (Z)-N-benzyl­idene-1-phenyl­methanamine oxide hydrogen peroxide monosolvate

Churakov, A.V.; Prikhodchenko, P.V.; Medvedev, A.G.; Mikhaylov, A.A.

doi:10.1107/S2056989017014499

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Volume 73| Part 11| November 2017| Pages 1666-1669

https://doi.org/10.1107/S2056989017014499

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Crystal structure of (Z)-N-benzylidene-1-phenylmethanamine oxide hydrogen peroxide monosolvate

Andrei V. Churakov,^a ^* Petr V. Prikhodchenko,^a Alexander G. Medvedev ^a and Alexey A. Mikhaylov ^a

^aInstitute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninskii prospekt 31, Moscow 119991, Russian Federation
^*Correspondence e-mail: churakov@igic.ras.ru

Edited by G. Smith, Queensland University of Technology, Australia (Received 29 September 2017; accepted 7 October 2017; online 20 October 2017)

The title adduct, C₁₄H₁₃NO·H₂O₂, consists of (Z)-N-benzylidene-1-phenylmethanamine oxide and hydrogen peroxide molecules in a 1:1 ratio. The organic coformer adopts a skew geometry with an inter-aryl-ring dihedral angle of 81.9 (2)°. In the crystal, the organic and peroxide molecules are linked through both peroxide O—H donor groups to oxide O-atom acceptors, giving one-dimensional chains extending along the b axis. Present also are weak intermolecular C—H⋯O hydrogen-bonding interactions.

Keywords: crystal structure; peroxosolvate; N-oxide; nitrone; hydrogen-bond motif.

CCDC reference: 1578615

1. Chemical context

Peroxosolvates are solid adducts that contain hydrogen peroxide molecules of crystallization in the same manner as the water in crystalline hydrates. Today, some of these are widely used as environmentally friendly bleaching compounds (Jakob et al., 2012 ) and oxidizing agents in organic synthesis (Ahn et al., 2015 ). Hydrogen bonding in peroxosolvates is of particular interest since it may be used for modelling of hydrogen peroxide behaviour in various significant biochemical processes (Kapustin et al., 2014 ).

It is known that nitrones R¹–CH=N(O)–R² [R¹, R² = aryl (Ar) or alkyl (Alk)] are readily available by oxidation of secondary amines using hydrogen peroxide (Goti et al., 2005 ). We supposed that the combination of oxidizing and cocrystallizing properties of hydrogen peroxide might afford an opportunity to obtain nitrone peroxosolvates in one step. We prepared the title 1:1 adduct of (Z)-N-benzylidene-1-phenylmethanamine oxide with hydrogen peroxide and the structure is reported herein.

2. Structural commentary

In the structure of the title adduct (Fig. 1), all bond lengths and angles in the organic coformer exhibit normal values for nitrone derivatives (Cambridge Structural Database, Version 5.38, May 2017; Groom et al., 2016 ). The nitrone fragment Ph—CH=N(O)—C is planar to within 0.128 (3) Å. It is almost perpendicular to the benzyl substituent C11–C17, with an O3—N1—C11—C12 torsion angle of 72.7 (4)°, and forms a dihedral angle between the two aryl rings of 81.9 (2)°. This is the same conformation as was previously observed in the structure of the pure coformer (Herrera et al., 2001 ). The organic molecule forms two hydrogen bonds, involving the negatively charged oxide atom O3, with adjacent peroxide molecules and the conformation is stabilized by an aromatic C27—H⋯O3 hydrogen bond (Table 1). As expected, the N1—O3⋯O(peroxo) angles are close to trigonal [117.9 (2) and 126.2 (2)°].

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯O3	1.05 (5)	1.66 (5)	2.707 (5)	174 (4)
O2—H2⋯O3ⁱ	1.06 (5)	1.64 (5)	2.681 (5)	166 (4)
C21—H21⋯O1ⁱⁱ	0.95	2.46	3.304 (6)	148
C27—H27⋯O3	0.95	2.29	2.902 (6)	121
C11—H111⋯O1ⁱⁱ	0.99	2.44	3.364 (7)	155
C11—H111⋯O2ⁱⁱ	0.99	2.47	3.394 (7)	155
C11—H112⋯O2	0.99	2.52	3.407 (7)	149
Symmetry codes: (i) x, y+1, z; (ii) $[x, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]$ .

Figure 1
The asymmetric unit in the title structure. Displacement ellipsoids are shown at the 50% probability level and the hydrogen bond is drawn as a dashed line.

In the peroxide molecule, the O—O distance is 1.467 (4) Å. This value is close to those previously observed in the accurately determined structures of crystalline hydrogen peroxide [1.461 (3) Å; Savariault et al., 1980 ] and urea perhydrate [1.4573 (8) Å; Fritchie & McMullan, 1981 ]. Partial substitutional disorder of hydrogen peroxide by water molecules (Pedersen, 1972 ) was not observed in the present structure since no residual peaks with an intensity of 0.14 e Å⁻³ were seen in the hydrogen peroxide molecule region (Churakov et al., 2005 ). The H₂O₂ molecule lies on a general position and presents a skew geometry, with the H—O—O—H torsion angle equal to 88 (4)°, and forms just two donor hydrogen bonds. It should be noted that the maximum possible number of hydrogen bonds formed by H₂O₂ is six (two donor and four acceptor; Chernyshov et al., 2017 ).

3. Supramolecular features

In the title crystal, the organic and peroxide molecules are linked into hydrogen-bonded chains extending along the b axis through charge-supported moderate HOOH⋯⁻O—N hydrogen bonds, with O⋯O separations of 2.707 (5) and 2.681 (5) Å (Table 1 and Fig. 2). Similar chains formed by N-oxide and H₂O₂ molecules were previously observed in the structure of risperidone N-oxide hydrogen peroxide methanol solvate (Ravikumar et al., 2005 ). In the present one-dimensional structure, minor weak non-aromatic C—H⋯O(peroxide) hydrogen-bonding interactions are also present.

Figure 2
Hydrogen-bonded chains extending along the b axis. H atoms on C atoms have been omitted for clarity. Hydrogen bonds are drawn as dashed lines.

4. Database survey

The Cambridge Structural Database (Groom et al., 2016) contains data for nine peroxosolvates of N- and P-oxides with one or two R₃X⁺ → O⁻ functional groups (X = N, P; R = Alk, Ar). It is of interest that all of these were obtained by oxidation of the corresponding amines (phosphines) using hydrogen peroxide, followed by immediate crystallization from the reaction mixtures. Analysis of the crystal packing for these compounds reveals three main supramolecular motifs (Fig. 3a–3c). Compounds BAFGOH (Ahn et al., 2015), BAFJUQ (Ahn et al., 2015), VANVOX (Hilliard et al., 2012 ) and XETSUK (Čermák et al., 2001 ) belong to type a [R₄²(10)]; compounds EKULUR (Chandrasekaran et al., 2002 ), TPPOPH (Thierbach et al., 1980 ) and UKEFEV (Sevcik et al., 2003 ) represent type b [D₂²(6)]. Finally, the title compound and DATHIQ (Ravikumar et al., 2005 ) are of type c [C₂¹(5)]. The relative simplicity of these motifs is caused by the absence of active H atoms in coformers of the aforementioned compounds. The special case is the three-dimensional structure of triethylenediamine N,N′-dioxide triperoxosolvate (FURFIH; Kay Hon & Mak, 1987 ).

Figure 3
Hydrogen-bonded motifs in the structures of N- and P-oxides.

5. Synthesis and crystallization

Needle-shaped crystals of the title compound crystallized spontaneously from a saturated solution of dibenzylamine in 50% hydrogen peroxide after holding for 3 d at room temperature. Caution! Handling procedures for concentrated hydrogen peroxide (danger of explosion) are described in detail by Wolanov et al. (2010).

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. Peroxide H atoms were found from a difference electron-density map and refined with individual isotropic displacement parameters and restrained O—H distances. All other H atoms were placed in calculated positions, with C—H = 0.95 (aromatic) or 0.99 Å (methylene), and treated as riding atoms, with relative isotropic displacement parameters U_iso(H) = 1.2U_eq(C).

Table 2
Experimental details

Crystal data
Chemical formula	C₁₄H₁₃NO·H₂O₂
M_r	245.27
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	150
a, b, c (Å)	21.802 (15), 4.597 (3), 12.742 (9)
β (°)	97.598 (11)
V (Å³)	1265.8 (16)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.09
Crystal size (mm)	0.40 × 0.04 × 0.04

Data collection
Diffractometer	Bruker SMART APEXII area-detector
Absorption correction	Multi-scan (SADABS; Bruker, 2008 )
T_min, T_max	0.965, 0.996
No. of measured, independent and observed [I > 2σ(I)] reflections	7458, 2227, 1113
R_int	0.108
(sin θ/λ)_max (Å⁻¹)	0.596

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.077, 0.218, 1.05
No. of reflections	2227
No. of parameters	172
No. of restraints	1
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.27, −0.26
Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008 ), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Supporting information

CCDC reference: 1578615

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S2056989017014499/zs2391sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989017014499/zs2391Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2056989017014499/zs2391Isup3.cml

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

(Z)-N-Benzylidene-1-phenylmethanamine oxide hydrogen peroxide monosolvate top

Crystal data top

C₁₄H₁₃NO·H₂O₂	F(000) = 520
M_r = 245.27	D_x = 1.287 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 737 reflections
a = 21.802 (15) Å	θ = 3.2–21.9°
b = 4.597 (3) Å	µ = 0.09 mm⁻¹
c = 12.742 (9) Å	T = 150 K
β = 97.598 (11)°	Needle, colourless
V = 1265.8 (16) Å³	0.40 × 0.04 × 0.04 mm
Z = 4

Data collection top

Bruker SMART APEXII area-detector diffractometer	2227 independent reflections
Radiation source: fine-focus sealed tube	1113 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.108
ω scans	θ_max = 25.1°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −25→25
T_min = 0.965, T_max = 0.996	k = −5→5
7458 measured reflections	l = −15→14

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: mixed
R[F² > 2σ(F²)] = 0.077	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.218	w = 1/[σ²(F_o²) + (0.1P)²] where P = (F_o² + 2F_c²)/3
S = 1.05	(Δ/σ)_max < 0.001
2227 reflections	Δρ_max = 0.27 e Å⁻³
172 parameters	Δρ_min = −0.26 e Å⁻³
1 restraint	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.034 (6)

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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 (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.23321 (15)	0.7522 (7)	1.0077 (3)	0.0427 (9)
O2	0.28942 (16)	0.9116 (7)	0.9911 (3)	0.0442 (10)
O3	0.22608 (15)	0.3093 (6)	0.8666 (2)	0.0377 (9)
N1	0.23366 (18)	0.3713 (7)	0.7676 (3)	0.0319 (10)
C11	0.2883 (2)	0.5529 (9)	0.7569 (4)	0.0342 (12)
H112	0.2894	0.7210	0.8057	0.041*
H111	0.2855	0.6284	0.6836	0.041*
C12	0.3463 (2)	0.3775 (9)	0.7821 (4)	0.0344 (12)
C13	0.3802 (2)	0.3866 (10)	0.8826 (4)	0.0438 (13)
H13	0.3672	0.5083	0.9356	0.053*
C14	0.4332 (2)	0.2183 (12)	0.9054 (5)	0.0573 (16)
H14	0.4563	0.2229	0.9741	0.069*
C15	0.4521 (3)	0.0431 (12)	0.8270 (5)	0.0592 (17)
H15	0.4888	−0.0694	0.8422	0.071*
C16	0.4190 (2)	0.0295 (12)	0.7281 (5)	0.0521 (15)
H16	0.4317	−0.0952	0.6756	0.063*
C17	0.3671 (2)	0.1997 (10)	0.7062 (4)	0.0423 (13)
H17	0.3447	0.1954	0.6370	0.051*
C21	0.1988 (2)	0.2713 (9)	0.6851 (4)	0.0334 (11)
H21	0.2083	0.3366	0.6184	0.040*
C22	0.1470 (2)	0.0714 (9)	0.6825 (4)	0.0330 (12)
C23	0.1155 (2)	0.0141 (11)	0.5825 (4)	0.0432 (13)
H23	0.1280	0.1064	0.5221	0.052*
C24	0.0658 (2)	−0.1774 (11)	0.5704 (4)	0.0480 (14)
H24	0.0438	−0.2129	0.5022	0.058*
C25	0.0486 (2)	−0.3157 (11)	0.6579 (4)	0.0479 (14)
H25	0.0149	−0.4481	0.6499	0.057*
C26	0.0800 (2)	−0.2629 (11)	0.7565 (4)	0.0443 (14)
H26	0.0681	−0.3606	0.8164	0.053*
C27	0.1284 (2)	−0.0708 (9)	0.7696 (4)	0.0356 (12)
H27	0.1495	−0.0341	0.8384	0.043*
H1	0.232 (2)	0.588 (9)	0.950 (4)	0.060 (15)*
H2	0.268 (2)	1.058 (10)	0.933 (4)	0.057 (15)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.054 (2)	0.0379 (19)	0.038 (2)	−0.0100 (17)	0.0135 (17)	−0.0039 (15)
O2	0.050 (2)	0.0394 (19)	0.044 (2)	−0.0075 (17)	0.0069 (18)	−0.0001 (16)
O3	0.052 (2)	0.0361 (17)	0.026 (2)	−0.0051 (15)	0.0106 (16)	0.0026 (14)
N1	0.041 (2)	0.027 (2)	0.029 (2)	0.0001 (18)	0.012 (2)	−0.0011 (17)
C11	0.041 (3)	0.033 (2)	0.029 (3)	−0.005 (2)	0.008 (2)	−0.001 (2)
C12	0.038 (3)	0.030 (2)	0.036 (3)	−0.007 (2)	0.006 (2)	0.004 (2)
C13	0.043 (3)	0.045 (3)	0.044 (4)	0.000 (3)	0.005 (3)	0.005 (2)
C14	0.047 (3)	0.064 (4)	0.058 (4)	0.003 (3)	−0.002 (3)	0.019 (3)
C15	0.052 (4)	0.048 (3)	0.080 (5)	0.004 (3)	0.020 (4)	0.016 (3)
C16	0.044 (3)	0.054 (3)	0.060 (4)	0.004 (3)	0.014 (3)	0.006 (3)
C17	0.042 (3)	0.043 (3)	0.043 (3)	−0.002 (3)	0.012 (3)	0.004 (2)
C21	0.038 (3)	0.031 (2)	0.031 (3)	0.004 (2)	0.001 (2)	0.001 (2)
C22	0.035 (3)	0.034 (2)	0.030 (3)	0.004 (2)	0.007 (2)	0.000 (2)
C23	0.046 (3)	0.047 (3)	0.035 (3)	0.000 (3)	0.004 (3)	−0.003 (2)
C24	0.039 (3)	0.056 (3)	0.046 (4)	−0.005 (3)	−0.005 (3)	−0.007 (3)
C25	0.042 (3)	0.051 (3)	0.053 (4)	−0.008 (3)	0.016 (3)	−0.013 (3)
C26	0.051 (3)	0.042 (3)	0.043 (3)	−0.002 (3)	0.017 (3)	−0.005 (2)
C27	0.033 (3)	0.038 (3)	0.037 (3)	−0.001 (2)	0.009 (2)	−0.004 (2)

Geometric parameters (Å, º) top

O1—O2	1.467 (4)	C16—C17	1.375 (7)
O1—H1	1.05 (4)	C16—H16	0.9500
O2—H2	1.06 (4)	C17—H17	0.9500
O3—N1	1.325 (4)	C21—C22	1.454 (6)
N1—C21	1.297 (6)	C21—H21	0.9500
N1—C11	1.475 (6)	C22—C23	1.390 (6)
C11—C12	1.498 (6)	C22—C27	1.393 (6)
C11—H112	0.9900	C23—C24	1.388 (7)
C11—H111	0.9900	C23—H23	0.9500
C12—C17	1.388 (6)	C24—C25	1.378 (7)
C12—C13	1.392 (7)	C24—H24	0.9500
C13—C14	1.388 (7)	C25—C26	1.371 (7)
C13—H13	0.9500	C25—H25	0.9500
C14—C15	1.389 (8)	C26—C27	1.368 (7)
C14—H14	0.9500	C26—H26	0.9500
C15—C16	1.368 (8)	C27—H27	0.9500
C15—H15	0.9500

O2—O1—H1	102 (3)	C17—C16—H16	120.6
O1—O2—H2	97 (3)	C16—C17—C12	122.0 (5)
C21—N1—O3	124.2 (4)	C16—C17—H17	119.0
C21—N1—C11	121.3 (4)	C12—C17—H17	119.0
O3—N1—C11	114.4 (4)	N1—C21—C22	127.8 (4)
N1—C11—C12	110.1 (3)	N1—C21—H21	116.1
N1—C11—H112	109.6	C22—C21—H21	116.1
C12—C11—H112	109.6	C23—C22—C27	118.8 (4)
N1—C11—H111	109.6	C23—C22—C21	115.4 (4)
C12—C11—H111	109.6	C27—C22—C21	125.8 (5)
H112—C11—H111	108.1	C24—C23—C22	120.3 (5)
C17—C12—C13	118.4 (5)	C24—C23—H23	119.8
C17—C12—C11	120.8 (5)	C22—C23—H23	119.8
C13—C12—C11	120.9 (4)	C25—C24—C23	119.6 (5)
C14—C13—C12	120.2 (5)	C25—C24—H24	120.2
C14—C13—H13	119.9	C23—C24—H24	120.2
C12—C13—H13	119.9	C26—C25—C24	120.2 (5)
C13—C14—C15	119.3 (6)	C26—C25—H25	119.9
C13—C14—H14	120.3	C24—C25—H25	119.9
C15—C14—H14	120.3	C27—C26—C25	120.6 (5)
C16—C15—C14	121.3 (6)	C27—C26—H26	119.7
C16—C15—H15	119.4	C25—C26—H26	119.7
C14—C15—H15	119.4	C26—C27—C22	120.4 (5)
C15—C16—C17	118.8 (5)	C26—C27—H27	119.8
C15—C16—H16	120.6	C22—C27—H27	119.8

C21—N1—C11—C12	−103.9 (5)	C11—N1—C21—C22	174.4 (4)
O3—N1—C11—C12	72.7 (4)	N1—C21—C22—C23	176.4 (4)
N1—C11—C12—C17	82.7 (5)	N1—C21—C22—C27	−6.0 (7)
N1—C11—C12—C13	−96.6 (5)	C27—C22—C23—C24	1.2 (7)
C17—C12—C13—C14	−0.7 (7)	C21—C22—C23—C24	179.0 (4)
C11—C12—C13—C14	178.7 (4)	C22—C23—C24—C25	−1.4 (7)
C12—C13—C14—C15	0.5 (7)	C23—C24—C25—C26	0.5 (7)
C13—C14—C15—C16	−1.1 (8)	C24—C25—C26—C27	0.6 (7)
C14—C15—C16—C17	1.8 (8)	C25—C26—C27—C22	−0.8 (7)
C15—C16—C17—C12	−2.0 (7)	C23—C22—C27—C26	−0.1 (7)
C13—C12—C17—C16	1.4 (7)	C21—C22—C27—C26	−177.6 (4)
C11—C12—C17—C16	−178.0 (4)	H1—O1—O2—H2	88 (4)
O3—N1—C21—C22	−1.8 (7)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O3	1.05 (5)	1.66 (5)	2.707 (5)	174 (4)
O2—H2···O3ⁱ	1.06 (5)	1.64 (5)	2.681 (5)	166 (4)
C21—H21···O1ⁱⁱ	0.95	2.46	3.304 (6)	148
C27—H27···O3	0.95	2.29	2.902 (6)	121
C11—H111···O1ⁱⁱ	0.99	2.44	3.364 (7)	155
C11—H111···O2ⁱⁱ	0.99	2.47	3.394 (7)	155
C11—H112···O2	0.99	2.52	3.407 (7)	149

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

Acknowledgements

X-ray diffraction studies were performed at the Centre of Shared Equipment of IGIC RAS. Publication was supported by the Federal Agency of Scientific Organizations within the State Assignment on Fundamental Research to the Kurnakov Institute of General and Inorganic Chemistry.

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