4-{[3-(4-Hydroxy-benzyl-ideneamino)-2,2-dimethyl-propyl]iminiomethyl}phenolate dihydrate.

The asymmetric unit of the title compound, C(19)H(22)N(2)O(2)·2H(2)O, comprises a zwitterionic form of the Schiff base compound and two water mol-ecules of crystallization. Inter-molecular N-H⋯O, C-H⋯O and O-H⋯N hydrogen bonds involving one of the water mol-ecules in the asymmetric unit generate seven- and eight-membered rings, with R(2) (1)(7) and R(2) (2)(8) ring motifs, respectively. The dihedral angle beween the two aromatic rings is 86.5 (2)°. The imino and iminium groups are coplanar with the benzene rings to which they are attached, making dihedral angles (N-C-C-C) of -179.3 (5) and -179.2 (4)°, respectively. Validation software indicates the higher symmetry space group Pnma for this structure. However, this process ignores H atoms and the zwitterionic configuration of the main mol-ecule breaks the higher symmetry. Solution in Pna2(1) provides a chemically sensible zwitterionic compound with improved residuals. In the crystal structure, mol-ecules are linked together through inter-molecular O-H⋯O, O-H⋯N, N-H⋯O and C-H⋯O inter-actions, forming a three-dimensional network. The crystal structure is further stabilized by inter-molecular C-H⋯π inter-actions.

Related literature

For hydrogen-bond motifs, see: Bernstein et al. (1995 ▶). For information on Schiff base ligands and their complexes and applications, see: Calligaris & Randaccio (1987 ▶); Li et al. (2005 ▶); Bomfim et al. (2005 ▶); Glidewell et al. (2005 ▶, 2006 ▶); Sun et al. (2004 ▶). For details of the synthesis, see: Fun et al. (2008 ▶). For the stability of the temperature controller used for data collection, see: Cosier & Glazer (1986 ▶).

Experimental

Crystal data

C19H22N2O2·2H2O

M = 346.42

Orthorhombic,

a = 13.0336 (4) Å

b = 11.5242 (3) Å

c = 12.4132 (4) Å

V = 1864.49 (10) Å3

Z = 4

Mo Kα radiation

μ = 0.09 mm−1

T = 100 K

0.34 × 0.21 × 0.11 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2005 ▶) T min = 0.971, T max = 0.991

10183 measured reflections

2237 independent reflections

1753 reflections with I > 2σ(I)

R int = 0.056

Refinement

R[F 2 > 2σ(F 2)] = 0.047

wR(F 2) = 0.116

S = 1.05

2237 reflections

235 parameters

3 restraints

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.27 e Å−3

Δρmin = −0.20 e Å−3

Data collection: APEX2 (Bruker, 2005 ▶); cell refinement: APEX2; data reduction: SAINT (Bruker, 2005 ▶); program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ▶).

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809013804/sj2615sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809013804/sj2615Isup2.hkl

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

C19H22N2O2·2H2O	F(000) = 744
Mr = 346.42	Dx = 1.234 Mg m−3
Orthorhombic, Pna21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2n	Cell parameters from 1477 reflections
a = 13.0336 (4) Å	θ = 2.4–29.9°
b = 11.5242 (3) Å	µ = 0.09 mm−1
c = 12.4132 (4) Å	T = 100 K
V = 1864.49 (10) Å3	Block, orange
Z = 4	0.34 × 0.21 × 0.11 mm

Bruker SMART APEXII CCD area-detector diffractometer	2237 independent reflections
Radiation source: fine-focus sealed tube	1753 reflections with I > 2σ(I)
graphite	Rint = 0.056
φ and ω scans	θmax = 27.5°, θmin = 2.4°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −15→16
Tmin = 0.971, Tmax = 0.991	k = −14→14
10183 measured reflections	l = −16→7

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)] = 0.047	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.116	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ2(Fo2) + (0.0526P)2 + 0.5548P] where P = (Fo2 + 2Fc2)/3
2237 reflections	(Δ/σ)max < 0.001
235 parameters	Δρmax = 0.27 e Å−3
3 restraints	Δρmin = −0.20 e Å−3

Experimental. The crystal was placed in the cold stream of an Oxford Cyrosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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.

	x	y	z	Uiso*/Ueq
O1	0.0498 (3)	0.5696 (3)	1.0250 (3)	0.0254 (8)
O2	0.0475 (3)	0.5792 (3)	0.4102 (2)	0.0217 (7)
N1	0.5104 (3)	0.5803 (3)	0.8323 (3)	0.0192 (8)
N2	0.5136 (3)	0.5842 (3)	0.5796 (3)	0.0186 (8)
C1	0.2946 (4)	0.5328 (4)	0.8831 (4)	0.0181 (10)
H1A	0.3225	0.4895	0.8270	0.022*
C2	0.1925 (4)	0.5165 (4)	0.9112 (4)	0.0178 (10)
H2A	0.1528	0.4627	0.8741	0.021*
C3	0.1496 (4)	0.5802 (4)	0.9947 (4)	0.0184 (10)
C4	0.2104 (4)	0.6615 (4)	1.0498 (4)	0.0221 (10)
H4A	0.1828	0.7050	1.1059	0.026*
C5	0.3115 (4)	0.6764 (4)	1.0197 (4)	0.0211 (10)
H5A	0.3510	0.7310	1.0560	0.025*
C6	0.3563 (4)	0.6130 (4)	0.9374 (4)	0.0181 (10)
C7	0.4645 (4)	0.6339 (4)	0.9073 (4)	0.0186 (10)
H7A	0.5010	0.6896	0.9457	0.022*
C8	0.6178 (4)	0.6143 (4)	0.8131 (4)	0.0172 (9)
H8A	0.6594	0.5447	0.8092	0.021*
H8B	0.6416	0.6593	0.8742	0.021*
C9	0.63477 (18)	0.6854 (2)	0.7101 (5)	0.0166 (5)
C10	0.6196 (4)	0.6143 (4)	0.6059 (4)	0.0207 (10)
H10A	0.6481	0.6580	0.5463	0.025*
H10B	0.6588	0.5431	0.6122	0.025*
C11	0.4577 (4)	0.6396 (3)	0.5096 (3)	0.0173 (9)
H11A	0.4891	0.7009	0.4737	0.021*
C12	0.3548 (4)	0.6168 (4)	0.4823 (4)	0.0160 (9)
C13	0.3087 (4)	0.6874 (4)	0.4023 (4)	0.0186 (10)
H13A	0.3476	0.7432	0.3668	0.022*
C14	0.2061 (4)	0.6736 (4)	0.3767 (4)	0.0183 (9)
H14A	0.1768	0.7206	0.3241	0.022*
C15	0.1448 (4)	0.5894 (4)	0.4291 (4)	0.0172 (9)
C16	0.1949 (4)	0.5154 (3)	0.5056 (4)	0.0182 (10)
H16A	0.1574	0.4564	0.5382	0.022*
C17	0.2949 (4)	0.5287 (3)	0.5318 (4)	0.0181 (10)
H17A	0.3246	0.4798	0.5826	0.022*
C18	0.56782 (19)	0.7944 (2)	0.7087 (5)	0.0209 (6)
H18A	0.5770	0.8364	0.7748	0.031*
H18B	0.4971	0.7725	0.7014	0.031*
H18C	0.5873	0.8426	0.6491	0.031*
C19	0.74958 (18)	0.7180 (2)	0.7099 (6)	0.0230 (6)
H19A	0.7659	0.7590	0.7750	0.034*
H19B	0.7640	0.7666	0.6490	0.034*
H19C	0.7903	0.6487	0.7057	0.034*
O1W	0.02979 (14)	0.33777 (16)	0.7189 (3)	0.0223 (5)
H1W1	0.0021	0.3754	0.6592	0.033*
H2W1	0.0012	0.3713	0.7731	0.033*
O2W	0.45692 (15)	0.38775 (16)	0.7030 (3)	0.0247 (5)
H1W2	0.4922	0.3279	0.6916	0.037*
H2W2	0.4735	0.4056	0.7681	0.037*
H1N2	0.487 (3)	0.520 (3)	0.618 (3)	0.020 (9)*
H1O1	0.020 (3)	0.524 (4)	0.984 (4)	0.040 (14)*

	U11	U22	U33	U12	U13	U23
O1	0.0152 (16)	0.0329 (16)	0.0281 (17)	−0.0051 (14)	0.0031 (13)	−0.0086 (14)
O2	0.0171 (16)	0.0261 (15)	0.0219 (16)	−0.0001 (13)	−0.0042 (13)	0.0062 (12)
N1	0.020 (2)	0.0172 (18)	0.0207 (18)	−0.0025 (17)	0.0044 (15)	0.0045 (16)
N2	0.0145 (19)	0.0181 (18)	0.0231 (19)	−0.0025 (16)	0.0018 (15)	−0.0003 (15)
C1	0.019 (2)	0.019 (2)	0.016 (2)	0.001 (2)	0.0061 (19)	0.0063 (18)
C2	0.018 (3)	0.020 (2)	0.015 (2)	−0.0032 (19)	−0.0010 (19)	0.0004 (17)
C3	0.012 (2)	0.0189 (19)	0.025 (2)	−0.0004 (17)	0.0006 (17)	0.0025 (18)
C4	0.022 (2)	0.0227 (19)	0.022 (2)	0.0024 (19)	0.0011 (19)	−0.0022 (18)
C5	0.026 (3)	0.0182 (18)	0.019 (2)	−0.0060 (19)	−0.004 (2)	0.0028 (18)
C6	0.021 (2)	0.0139 (18)	0.019 (2)	0.0006 (19)	0.0014 (18)	0.0042 (19)
C7	0.0090 (19)	0.024 (2)	0.023 (2)	−0.0051 (17)	−0.0087 (18)	0.0076 (18)
C8	0.010 (2)	0.017 (2)	0.025 (2)	0.0022 (19)	−0.0017 (18)	0.004 (2)
C9	0.0150 (11)	0.0190 (11)	0.0157 (13)	−0.0035 (10)	0.002 (2)	−0.004 (2)
C10	0.021 (2)	0.025 (2)	0.016 (2)	−0.004 (2)	−0.0033 (19)	0.000 (2)
C11	0.029 (2)	0.0100 (16)	0.013 (2)	0.0029 (18)	−0.0015 (18)	−0.0009 (15)
C12	0.012 (2)	0.0166 (18)	0.020 (2)	0.0025 (18)	0.0026 (17)	−0.0080 (19)
C13	0.018 (2)	0.0142 (17)	0.024 (2)	−0.0012 (17)	0.0025 (19)	0.0039 (17)
C14	0.023 (2)	0.0161 (18)	0.016 (2)	0.0023 (18)	0.0008 (19)	0.0027 (17)
C15	0.021 (2)	0.0144 (16)	0.017 (2)	0.0029 (18)	−0.0014 (18)	−0.0027 (17)
C16	0.018 (3)	0.0117 (18)	0.025 (3)	0.0003 (18)	0.0044 (19)	0.0002 (18)
C17	0.021 (2)	0.0116 (17)	0.022 (2)	0.0041 (18)	0.0054 (19)	0.0051 (18)
C18	0.0220 (12)	0.0170 (12)	0.0238 (15)	−0.0011 (10)	−0.001 (3)	−0.006 (2)
C19	0.0181 (12)	0.0244 (13)	0.0265 (16)	−0.0061 (11)	0.002 (3)	0.001 (3)
O1W	0.0244 (10)	0.0209 (9)	0.0216 (13)	0.0046 (8)	−0.0003 (16)	−0.0010 (13)
O2W	0.0286 (11)	0.0201 (9)	0.0255 (14)	0.0002 (8)	−0.0010 (18)	−0.0041 (16)

O1—C3	1.359 (6)	C9—C10	1.543 (7)
O1—H1O1	0.83 (4)	C10—H10A	0.9700
O2—C15	1.295 (6)	C10—H10B	0.9700
N1—C7	1.267 (6)	C11—C12	1.407 (7)
N1—C8	1.473 (6)	C11—H11A	0.9300
N2—C11	1.302 (6)	C12—C13	1.418 (6)
N2—C10	1.461 (6)	C12—C17	1.421 (6)
N2—H1N2	0.95 (4)	C13—C14	1.384 (8)
C1—C2	1.388 (7)	C13—H13A	0.9300
C1—C6	1.398 (7)	C14—C15	1.415 (7)
C1—H1A	0.9300	C14—H14A	0.9300
C2—C3	1.387 (6)	C15—C16	1.434 (6)
C2—H2A	0.9300	C16—C17	1.352 (7)
C3—C4	1.405 (7)	C16—H16A	0.9300
C4—C5	1.380 (8)	C17—H17A	0.9300
C4—H4A	0.9300	C18—H18A	0.9600
C5—C6	1.385 (7)	C18—H18B	0.9600
C5—H5A	0.9300	C18—H18C	0.9600
C6—C7	1.480 (6)	C19—H19A	0.9600
C7—H7A	0.9300	C19—H19B	0.9600
C8—C9	1.535 (7)	C19—H19C	0.9600
C8—H8A	0.9700	O1W—H1W1	0.9309
C8—H8B	0.9700	O1W—H2W1	0.8614
C9—C18	1.529 (3)	O2W—H1W2	0.8404
C9—C19	1.543 (3)	O2W—H2W2	0.8612
C3—O1—H1O1	110 (4)	C9—C10—H10A	108.3
C7—N1—C8	115.9 (4)	N2—C10—H10B	108.3
C11—N2—C10	124.2 (4)	C9—C10—H10B	108.3
C11—N2—H1N2	121 (2)	H10A—C10—H10B	107.4
C10—N2—H1N2	115 (2)	N2—C11—C12	127.0 (4)
C2—C1—C6	121.3 (4)	N2—C11—H11A	116.5
C2—C1—H1A	119.4	C12—C11—H11A	116.5
C6—C1—H1A	119.4	C11—C12—C13	117.7 (4)
C3—C2—C1	120.2 (4)	C11—C12—C17	123.6 (4)
C3—C2—H2A	119.9	C13—C12—C17	118.7 (4)
C1—C2—H2A	119.9	C14—C13—C12	120.3 (4)
O1—C3—C2	123.0 (4)	C14—C13—H13A	119.8
O1—C3—C4	117.7 (4)	C12—C13—H13A	119.8
C2—C3—C4	119.3 (4)	C13—C14—C15	121.3 (4)
C5—C4—C3	119.3 (5)	C13—C14—H14A	119.4
C5—C4—H4A	120.3	C15—C14—H14A	119.4
C3—C4—H4A	120.3	O2—C15—C14	122.1 (4)
C4—C5—C6	122.4 (4)	O2—C15—C16	120.8 (4)
C4—C5—H5A	118.8	C14—C15—C16	117.1 (4)
C6—C5—H5A	118.8	C17—C16—C15	122.0 (4)
C5—C6—C1	117.5 (4)	C17—C16—H16A	119.0
C5—C6—C7	120.1 (4)	C15—C16—H16A	119.0
C1—C6—C7	122.3 (4)	C16—C17—C12	120.5 (4)
N1—C7—C6	123.8 (4)	C16—C17—H17A	119.8
N1—C7—H7A	118.1	C12—C17—H17A	119.8
C6—C7—H7A	118.1	C9—C18—H18A	109.5
N1—C8—C9	114.5 (3)	C9—C18—H18B	109.5
N1—C8—H8A	108.6	H18A—C18—H18B	109.5
C9—C8—H8A	108.6	C9—C18—H18C	109.5
N1—C8—H8B	108.6	H18A—C18—H18C	109.5
C9—C8—H8B	108.6	H18B—C18—H18C	109.5
H8A—C8—H8B	107.6	C9—C19—H19A	109.5
C18—C9—C8	111.4 (4)	C9—C19—H19B	109.5
C18—C9—C19	110.7 (2)	H19A—C19—H19B	109.5
C8—C9—C19	105.7 (4)	C9—C19—H19C	109.5
C18—C9—C10	110.7 (4)	H19A—C19—H19C	109.5
C8—C9—C10	113.3 (2)	H19B—C19—H19C	109.5
C19—C9—C10	104.6 (4)	H1W1—O1W—H2W1	104.2
N2—C10—C9	115.8 (4)	H1W2—O2W—H2W2	102.5
N2—C10—H10A	108.3
C6—C1—C2—C3	−0.1 (7)	C11—N2—C10—C9	99.7 (5)
C1—C2—C3—O1	178.9 (4)	C18—C9—C10—N2	−53.5 (5)
C1—C2—C3—C4	0.4 (7)	C8—C9—C10—N2	72.5 (4)
O1—C3—C4—C5	−178.6 (4)	C19—C9—C10—N2	−172.8 (4)
C2—C3—C4—C5	0.0 (7)	C10—N2—C11—C12	−178.4 (4)
C3—C4—C5—C6	−0.7 (7)	N2—C11—C12—C13	−179.2 (4)
C4—C5—C6—C1	0.9 (7)	N2—C11—C12—C17	1.9 (7)
C4—C5—C6—C7	179.0 (4)	C11—C12—C13—C14	−176.2 (4)
C2—C1—C6—C5	−0.6 (7)	C17—C12—C13—C14	2.8 (7)
C2—C1—C6—C7	−178.6 (4)	C12—C13—C14—C15	−0.1 (7)
C8—N1—C7—C6	179.1 (4)	C13—C14—C15—O2	176.4 (4)
C5—C6—C7—N1	−179.3 (4)	C13—C14—C15—C16	−3.1 (7)
C1—C6—C7—N1	−1.3 (7)	O2—C15—C16—C17	−175.9 (5)
C7—N1—C8—C9	−106.9 (4)	C14—C15—C16—C17	3.6 (7)
N1—C8—C9—C18	56.0 (4)	C15—C16—C17—C12	−1.0 (7)
N1—C8—C9—C19	176.4 (4)	C11—C12—C17—C16	176.6 (4)
N1—C8—C9—C10	−69.6 (4)	C13—C12—C17—C16	−2.3 (7)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1W1···O1i	0.93	1.91	2.830 (5)	171
O1W—H2W1···O2ii	0.86	1.90	2.751 (4)	168
O2W—H1W2···O1Wiii	0.84	2.00	2.774 (3)	153
O2W—H2W2···N1	0.86	2.22	2.826 (4)	127
N2—H1N2···O2W	0.95 (4)	1.90 (4)	2.832 (4)	170 (3)
O1—H1O1···O2ii	0.83 (4)	1.74 (5)	2.565 (5)	174 (5)
C17—H17A···O2W	0.93	2.52	3.408 (6)	161
C10—H10B···Cg1iv	0.97	2.69	3.422 (5)	133
C8—H8A···Cg2v	0.97	2.74	3.497 (5)	136

Table 1

Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of the C1–C6 and C12–C17 benzene rings, respectively.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1W—H1W1⋯O1i	0.93	1.91	2.830 (5)	171
O1W—H2W1⋯O2ii	0.86	1.90	2.751 (4)	168
O2W—H1W2⋯O1Wiii	0.84	2.00	2.774 (3)	153
O2W—H2W2⋯N1	0.86	2.22	2.826 (4)	127
N2—H1N2⋯O2W	0.95 (4)	1.90 (4)	2.832 (4)	170 (3)
O1—H1O1⋯O2ii	0.83 (4)	1.74 (5)	2.565 (5)	174 (5)
C17—H17A⋯O2W	0.93	2.52	3.408 (6)	161
C10—H10B⋯Cg1iv	0.97	2.69	3.422 (5)	133
C8—H8A⋯Cg2v	0.97	2.74	3.497 (5)	136

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) ; (v) .