2-[(2,4-Dimethyl-phen-yl)imino-meth-yl]-3,5-dimethoxy-phenol.

X-ray analysis reveals that the title Schiff base compound, C(17)H(19)NO(3), possesses both OH and NH tautomeric character in its mol-ecular structure. The occupancies of the enol and keto tautomers are 0.62 (3) and 0.38 (3), respectively. The presence of the minor keto form could not be confirmed from the IR spectrum. The mol-ecule is approximately planar, the dihedral angle between the planes of the two aromatic rings being 6.97 (8)°. The mol-ecular structure of the major component is stabilized by an intra-molecular O-H⋯N hydrogen bond, which generates an S(6) ring motif (N-H⋯O hydrogen bond in the minor component).

Related literature

For tautomeric forms of Schiff bases, see: Becker et al. (1987 ▶); Seliger et al. (1990 ▶); Sugawara et al. (1999 ▶); Tezer & Karakus (2009 ▶). For bond-length data, see: Allen et al. (1987 ▶); Ogawa & Harada (2003 ▶).

Experimental

Crystal data

C17H19NO3

M = 285.33

Monoclinic,

a = 4.7070 (2) Å

b = 11.283 (5) Å

c = 28.216 (5) Å

β = 97.542 (11)°

V = 1485.6 (7) Å3

Z = 4

Mo Kα radiation

μ = 0.09 mm−1

T = 296 K

0.67 × 0.31 × 0.09 mm

Data collection

Stoe IPDS II diffractometer

Absorption correction: integration (X-RED32; Stoe & Cie, 2002 ▶) T min = 0.977, T max = 0.994

13316 measured reflections

2797 independent reflections

1808 reflections with I > 2σ(I)

R int = 0.043

Refinement

R[F 2 > 2σ(F 2)] = 0.043

wR(F 2) = 0.111

S = 0.98

2797 reflections

195 parameters

H-atom parameters constrained

Δρmax = 0.09 e Å−3

Δρmin = −0.14 e Å−3

Data collection: X-AREA (Stoe & Cie, 2002 ▶); cell refinement: X-AREA; data reduction: X-RED32; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶).

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809021278/ci2808sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809021278/ci2808Isup2.hkl

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

C17H19NO3	F(000) = 608
Mr = 285.33	Dx = 1.276 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71069 Å
Hall symbol: -P 2ybc	Cell parameters from 10962 reflections
a = 4.7070 (2) Å	θ = 1.5–26.2°
b = 11.283 (5) Å	µ = 0.09 mm−1
c = 28.216 (5) Å	T = 296 K
β = 97.542 (11)°	Prism, yellow
V = 1485.6 (7) Å3	0.67 × 0.31 × 0.09 mm
Z = 4

Stoe IPDS II diffractometer	2797 independent reflections
Radiation source: fine-focus sealed tube	1808 reflections with I > 2σ(I)
plane graphite	Rint = 0.043
Detector resolution: 6.67 pixels mm-1	θmax = 25.6°, θmin = 1.5°
rotation method scans	h = −5→5
Absorption correction: integration (X-RED32; Stoe & Cie, 2002)	k = −13→13
Tmin = 0.977, Tmax = 0.994	l = −34→34
13316 measured reflections

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)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.111	H-atom parameters constrained
S = 0.98	w = 1/[σ2(Fo2) + (0.0599P)2] where P = (Fo2 + 2Fc2)/3
2797 reflections	(Δ/σ)max = 0.001
195 parameters	Δρmax = 0.09 e Å−3
0 restraints	Δρmin = −0.14 e Å−3

Experimental. 240 frames, detector distance = 130 mm

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.

	x	y	z	Uiso*/Ueq	Occ. (<1)
O1	−0.1970 (3)	0.07461 (10)	0.06735 (5)	0.0759 (4)
H1A	−0.0686	0.0847	0.0896	0.114*	0.62 (3)
O2	−0.3588 (3)	0.47471 (10)	0.10480 (4)	0.0735 (4)
O3	−0.9431 (3)	0.29177 (10)	−0.02381 (4)	0.0721 (4)
N1	0.1167 (3)	0.18286 (12)	0.13482 (5)	0.0584 (4)
H1B	0.0796	0.1207	0.1175	0.070*	0.38 (3)
C1	−0.2694 (3)	0.27691 (13)	0.08638 (6)	0.0534 (4)
C2	−0.3428 (4)	0.17509 (14)	0.05865 (6)	0.0580 (4)
C3	−0.5703 (4)	0.17634 (14)	0.02150 (6)	0.0610 (5)
H3	−0.6186	0.1085	0.0035	0.073*
C4	−0.7208 (3)	0.27934 (14)	0.01202 (6)	0.0569 (4)
C5	−0.6564 (4)	0.38249 (14)	0.03878 (6)	0.0593 (4)
H5	−0.7616	0.4515	0.0317	0.071*
C6	−0.4362 (3)	0.38028 (13)	0.07557 (6)	0.0553 (4)
C7	−0.0392 (3)	0.27603 (14)	0.12467 (6)	0.0565 (4)
H7	−0.0002	0.3443	0.1428	0.068*
C8	0.3450 (3)	0.17699 (14)	0.17280 (6)	0.0555 (4)
C9	0.4693 (3)	0.06605 (15)	0.18298 (6)	0.0590 (4)
C10	0.6896 (4)	0.05720 (16)	0.22082 (6)	0.0657 (5)
H10	0.7713	−0.0168	0.2279	0.079*
C11	0.7925 (4)	0.15256 (17)	0.24829 (6)	0.0655 (5)
C12	0.6723 (4)	0.26180 (17)	0.23629 (7)	0.0694 (5)
H12	0.7412	0.3283	0.2536	0.083*
C13	0.4512 (4)	0.27460 (16)	0.19910 (6)	0.0661 (5)
H13	0.3736	0.3492	0.1918	0.079*
C14	0.3707 (4)	−0.04062 (15)	0.15315 (7)	0.0758 (6)
H14A	0.4782	−0.1089	0.1653	0.114*
H14B	0.4005	−0.0269	0.1206	0.114*
H14C	0.1706	−0.0540	0.1546	0.114*
C15	1.0290 (4)	0.1388 (2)	0.28958 (7)	0.0865 (6)
H15A	0.9977	0.1930	0.3146	0.130*	0.50
H15B	1.2103	0.1555	0.2789	0.130*	0.50
H15C	1.0293	0.0590	0.3015	0.130*	0.50
H15D	1.1605	0.0787	0.2821	0.130*	0.50
H15E	0.9479	0.1162	0.3177	0.130*	0.50
H15F	1.1289	0.2127	0.2952	0.130*	0.50
C16	−0.5298 (4)	0.57876 (15)	0.09754 (7)	0.0788 (6)
H16A	−0.4572	0.6380	0.1204	0.118*
H16B	−0.7242	0.5602	0.1015	0.118*
H16C	−0.5232	0.6082	0.0658	0.118*
C17	−1.0150 (5)	0.19050 (17)	−0.05323 (8)	0.0852 (7)
H17A	−1.1735	0.2093	−0.0770	0.128*
H17B	−1.0670	0.1261	−0.0339	0.128*
H17C	−0.8529	0.1679	−0.0686	0.128*

	U11	U22	U33	U12	U13	U23
O1	0.0732 (8)	0.0612 (7)	0.0852 (9)	0.0155 (6)	−0.0198 (7)	−0.0036 (7)
O2	0.0791 (9)	0.0578 (7)	0.0746 (8)	0.0127 (6)	−0.0235 (7)	−0.0093 (6)
O3	0.0703 (8)	0.0676 (7)	0.0697 (8)	0.0140 (6)	−0.0237 (6)	−0.0097 (6)
N1	0.0537 (8)	0.0624 (8)	0.0559 (8)	0.0062 (6)	−0.0046 (7)	0.0033 (6)
C1	0.0488 (9)	0.0570 (9)	0.0529 (9)	0.0024 (7)	0.0002 (7)	0.0055 (7)
C2	0.0541 (10)	0.0562 (9)	0.0613 (10)	0.0076 (7)	−0.0010 (8)	0.0058 (8)
C3	0.0585 (10)	0.0574 (9)	0.0635 (10)	0.0047 (8)	−0.0058 (8)	−0.0043 (8)
C4	0.0513 (9)	0.0615 (9)	0.0548 (10)	0.0041 (7)	−0.0048 (8)	0.0020 (8)
C5	0.0575 (10)	0.0553 (9)	0.0616 (10)	0.0094 (7)	−0.0054 (8)	0.0037 (8)
C6	0.0555 (10)	0.0538 (8)	0.0545 (9)	0.0004 (7)	−0.0009 (8)	0.0006 (7)
C7	0.0534 (9)	0.0598 (9)	0.0549 (10)	0.0010 (8)	0.0009 (8)	0.0021 (7)
C8	0.0476 (9)	0.0671 (10)	0.0499 (9)	0.0022 (7)	−0.0013 (7)	0.0033 (8)
C9	0.0538 (10)	0.0672 (10)	0.0542 (10)	0.0052 (8)	0.0008 (8)	0.0053 (8)
C10	0.0570 (10)	0.0762 (11)	0.0614 (11)	0.0099 (8)	−0.0018 (9)	0.0105 (9)
C11	0.0494 (10)	0.0920 (13)	0.0531 (10)	0.0037 (9)	−0.0002 (8)	0.0085 (9)
C12	0.0607 (11)	0.0834 (12)	0.0613 (11)	−0.0051 (9)	−0.0023 (9)	−0.0070 (9)
C13	0.0595 (11)	0.0696 (10)	0.0661 (11)	0.0056 (8)	−0.0034 (9)	−0.0001 (9)
C14	0.0810 (13)	0.0660 (11)	0.0750 (12)	0.0091 (9)	−0.0097 (10)	0.0030 (9)
C15	0.0623 (12)	0.1271 (17)	0.0645 (12)	−0.0006 (11)	−0.0125 (10)	0.0102 (12)
C16	0.0879 (14)	0.0586 (10)	0.0823 (13)	0.0180 (9)	−0.0175 (11)	−0.0103 (9)
C17	0.0864 (14)	0.0770 (12)	0.0816 (13)	0.0157 (10)	−0.0293 (11)	−0.0214 (10)

O1—C2	1.3312 (18)	C10—C11	1.376 (3)
O1—H1A	0.82	C10—H10	0.93
O2—C6	1.3673 (19)	C11—C12	1.380 (3)
O2—C16	1.4229 (19)	C11—C15	1.510 (2)
O3—C4	1.3634 (18)	C12—C13	1.385 (2)
O3—C17	1.427 (2)	C12—H12	0.93
N1—C7	1.293 (2)	C13—H13	0.93
N1—C8	1.4159 (19)	C14—H14A	0.96
N1—H1B	0.86	C14—H14B	0.96
C1—C2	1.407 (2)	C14—H14C	0.96
C1—C6	1.416 (2)	C15—H15A	0.96
C1—C7	1.426 (2)	C15—H15B	0.96
C2—C3	1.397 (2)	C15—H15C	0.96
C3—C4	1.369 (2)	C15—H15D	0.96
C3—H3	0.93	C15—H15E	0.96
C4—C5	1.399 (2)	C15—H15F	0.96
C5—C6	1.367 (2)	C16—H16A	0.96
C5—H5	0.93	C16—H16B	0.96
C7—H7	0.93	C16—H16C	0.96
C8—C13	1.384 (2)	C17—H17A	0.96
C8—C9	1.396 (2)	C17—H17B	0.96
C9—C10	1.391 (2)	C17—H17C	0.96
C9—C14	1.507 (2)
C2—O1—H1A	109.5	C8—C13—C12	120.38 (17)
C6—O2—C16	117.08 (12)	C8—C13—H13	119.8
C4—O3—C17	116.70 (13)	C12—C13—H13	119.8
C7—N1—C8	123.93 (15)	C9—C14—H14A	109.5
C7—N1—H1B	118.0	C9—C14—H14B	109.5
C8—N1—H1B	118.0	H14A—C14—H14B	109.5
C2—C1—C6	117.64 (14)	C9—C14—H14C	109.5
C2—C1—C7	121.47 (14)	H14A—C14—H14C	109.5
C6—C1—C7	120.88 (14)	H14B—C14—H14C	109.5
O1—C2—C3	118.22 (14)	C11—C15—H15A	109.5
O1—C2—C1	120.65 (14)	C11—C15—H15B	109.5
C3—C2—C1	121.13 (14)	H15A—C15—H15B	109.5
C4—C3—C2	118.77 (15)	C11—C15—H15C	109.5
C4—C3—H3	120.6	H15A—C15—H15C	109.5
C2—C3—H3	120.6	H15B—C15—H15C	109.5
O3—C4—C3	124.01 (14)	C11—C15—H15D	109.5
O3—C4—C5	113.93 (13)	H15A—C15—H15D	141.1
C3—C4—C5	122.06 (14)	H15B—C15—H15D	56.3
C6—C5—C4	118.92 (14)	H15C—C15—H15D	56.3
C6—C5—H5	120.5	C11—C15—H15E	109.5
C4—C5—H5	120.5	H15A—C15—H15E	56.3
O2—C6—C5	124.00 (14)	H15B—C15—H15E	141.1
O2—C6—C1	114.55 (13)	H15C—C15—H15E	56.3
C5—C6—C1	121.46 (15)	H15D—C15—H15E	109.5
N1—C7—C1	121.77 (15)	C11—C15—H15F	109.5
N1—C7—H7	119.1	H15A—C15—H15F	56.3
C1—C7—H7	119.1	H15B—C15—H15F	56.3
C13—C8—C9	119.42 (15)	H15C—C15—H15F	141.1
C13—C8—N1	123.59 (15)	H15D—C15—H15F	109.5
C9—C8—N1	116.99 (14)	H15E—C15—H15F	109.5
C10—C9—C8	118.20 (16)	O2—C16—H16A	109.5
C10—C9—C14	121.02 (15)	O2—C16—H16B	109.5
C8—C9—C14	120.76 (14)	H16A—C16—H16B	109.5
C11—C10—C9	123.23 (17)	O2—C16—H16C	109.5
C11—C10—H10	118.4	H16A—C16—H16C	109.5
C9—C10—H10	118.4	H16B—C16—H16C	109.5
C10—C11—C12	117.21 (16)	O3—C17—H17A	109.5
C10—C11—C15	121.56 (18)	O3—C17—H17B	109.5
C12—C11—C15	121.23 (18)	H17A—C17—H17B	109.5
C11—C12—C13	121.49 (17)	O3—C17—H17C	109.5
C11—C12—H12	119.3	H17A—C17—H17C	109.5
C13—C12—H12	119.3	H17B—C17—H17C	109.5
C6—C1—C2—O1	−179.15 (16)	C7—C1—C6—C5	179.61 (16)
C7—C1—C2—O1	−0.4 (3)	C8—N1—C7—C1	−179.15 (15)
C6—C1—C2—C3	0.6 (3)	C2—C1—C7—N1	1.8 (3)
C7—C1—C2—C3	179.39 (17)	C6—C1—C7—N1	−179.44 (15)
O1—C2—C3—C4	−179.62 (16)	C7—N1—C8—C13	−9.1 (3)
C1—C2—C3—C4	0.6 (3)	C7—N1—C8—C9	172.11 (16)
C17—O3—C4—C3	−1.3 (3)	C13—C8—C9—C10	2.6 (3)
C17—O3—C4—C5	178.46 (17)	N1—C8—C9—C10	−178.54 (15)
C2—C3—C4—O3	178.77 (17)	C13—C8—C9—C14	−176.31 (17)
C2—C3—C4—C5	−0.9 (3)	N1—C8—C9—C14	2.6 (2)
O3—C4—C5—C6	−179.76 (16)	C8—C9—C10—C11	−0.7 (3)
C3—C4—C5—C6	0.0 (3)	C14—C9—C10—C11	178.17 (18)
C16—O2—C6—C5	3.4 (3)	C9—C10—C11—C12	−1.5 (3)
C16—O2—C6—C1	−176.22 (17)	C9—C10—C11—C15	179.01 (18)
C4—C5—C6—O2	−178.32 (16)	C10—C11—C12—C13	1.9 (3)
C4—C5—C6—C1	1.3 (3)	C15—C11—C12—C13	−178.59 (18)
C2—C1—C6—O2	178.09 (15)	C9—C8—C13—C12	−2.2 (3)
C7—C1—C6—O2	−0.7 (2)	N1—C8—C13—C12	178.98 (17)
C2—C1—C6—C5	−1.6 (3)	C11—C12—C13—C8	−0.1 (3)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1A···N1	0.82	1.82 (1)	2.561 (2)	149
N1—H1B···O1	0.86	1.86 (1)	2.561 (2)	137 (1)

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1A⋯N1	0.82	1.82 (1)	2.561 (2)	149
N1—H1B⋯O1	0.86	1.86 (1)	2.561 (2)	137 (1)