2-Bromo-4-tert-butyl-6-[(pyridin-2-yl­imino)­meth­yl]phenol

Balasubramani, V.; Vinuchakkaravarthy, T.; Gopi, S.; Narasimhan, S.; Velmurugan, D.

doi:10.1107/S1600536811050148

organic compounds

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ISSN: 2056-9890

Volume 67| Part 12| December 2011| Page o3483

https://doi.org/10.1107/S1600536811050148

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2-Bromo-4-tert-butyl-6-[(pyridin-2-ylimino)methyl]phenol

V. Balasubramani,^a T. Vinuchakkaravarthy,^b Sreeraj Gopi,^a S. Narasimhan ^a and D. Velmurugan ^b ^*

^aAsthagiri Herbal Research Foundation, 162-A, Industrial Estate, Perungudi, Chennai 600 092, India, and ^bCentre of Advanced Study in Crystallography and Biophysics, University of Madras, Maraimalai Campus (Guindy Campus), Chennai 600 025, India
^*Correspondence e-mail: shirai2011@gmail.com

(Received 11 November 2011; accepted 22 November 2011; online 30 November 2011)

In the title compound, C₁₆H₁₇BrN₂O, the pyridine and benzene rings are almost coplanar [dihedral angle = 1.3 (2)°]. An intramolecular O—H⋯Br interaction forms an S(5) ring motif.

Related literature

For the anti-bacterial and anti-tumor activity of substituted salicylaldehyde derivatives, see: Jesmin et al. (2010 ); Pelttari et al. (2007 ) and for the biological activity of 2-aminopryidine derivatives, see: Hagmann et al. (2000 ). For related structures, see: Puthilibai et al. (2008 ); Phurat et al. (2010 ); Wang et al.(2010 ). For the synthesis, see: Pannerselvam et al. (2005 ).

Experimental

Crystal data

C₁₆H₁₇BrN₂O
M_r = 333.23
Monoclinic, C c
a = 10.0241 (11) Å
b = 16.1355 (16) Å
c = 9.4308 (13) Å
β = 92.050 (6)°
V = 1524.4 (3) Å³
Z = 4
Mo Kα radiation
μ = 2.69 mm⁻¹
T = 293 K
0.2 × 0.2 × 0.2 mm

Data collection

Bruker SMART APEXII area-detector diffractometer
6913 measured reflections
3051 independent reflections
2564 reflections with I > 2σ(I)
R_int = 0.035

Refinement

R[F² > 2σ(F²)] = 0.033
wR(F²) = 0.081
S = 0.98
3051 reflections
184 parameters
2 restraints
H-atom parameters constrained
Δρ_max = 0.50 e Å⁻³
Δρ_min = −0.37 e Å⁻³
Absolute structure: Flack (1983 ), 1147 Friedel pairs
Flack parameter: 0.009 (9)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯Br1	0.82	2.46	3.021 (3)	127

Data collection: APEX2 (Bruker, 2008 ); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536811050148/im2341sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811050148/im2341Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536811050148/im2341Isup3.cml

checkCIF report

Comment top

The crystal structure determination of the title compound was undertaken as a part of the synthesis, structure and properties of new class of substituted salicylaldehyde derivatives.

In the crystal structure the pyridine ring and the substituted phenyl rings are essentially co-planar with a mean deviation of 0.0057Å and 0.0053Å, respectively, from the least square planes of the corresponding constituent ring atoms. Unlike the other structures, the N(1) atom of the pyridine ring aligns with the plane of the other atoms contributing the ring (C12—C13—C14—C15—C16). The dihedral angle between pyridine ring and the phenyl ring is 1.3 (2)°. The Br(1) atom is almost co-planar with the phenyl ring (C1 to C6) with a mean deviation of 0.025 (1)Å. An intramolecular O(1)—H···Br(1) hydrogen bond forms a S(5) ring motif. Intramolecular C(7)—H···N(2) weak interaction is also observed in the structure.

Related literature top

For the anti-bacterial and anti-tumor activity of substituted salicylaldehyde derivatives, see: Jesmin et al. (2010); Pelttari et al. (2007) and for the biological activity of 2-aminopryidine derivatives, see: Hagmann et al. (2000). For related structures, see: Puthilibai et al. (2008); Phurat et al. (2010); Wang et al.(2010). For the synthesis, see: Pannerselvam et al. (2005).

Experimental top

The synthesis of the title compound follows the modified method of Schiff's base prepartion described by Pannerselvam et al. (2005). The microwave-assisted condensation of 3-bromo-5-tert-btuyl-2-hydroxybenzaldehyde and 2-amino pyridine was carried out in a domestic oven, Samsung SMH9151BE. Equimolar concentrations of 3-bromo-5-tert-butyl-2-hydroxy benzaldehyde and 2-amino pyridine (3mmol each) were dissolved in anhydrous methanol (5mL) at ambient temperature in an 25mL Erlenmeyer flask. The mixture was subjected to microwave irradiation for an optimized time (8 mins) on the M-High setting (800W). It was then cooled and diluted with ice-cold water. The product yield was found to be 72% and the purity was checked using TLC. The compound was re-crystallized from methanol/water mixture at room temperature to yield single crystals.

Structure description top

The crystal structure determination of the title compound was undertaken as a part of the synthesis, structure and properties of new class of substituted salicylaldehyde derivatives.

For the anti-bacterial and anti-tumor activity of substituted salicylaldehyde derivatives, see: Jesmin et al. (2010); Pelttari et al. (2007) and for the biological activity of 2-aminopryidine derivatives, see: Hagmann et al. (2000). For related structures, see: Puthilibai et al. (2008); Phurat et al. (2010); Wang et al.(2010). For the synthesis, see: Pannerselvam et al. (2005).

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: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

Fig. 1. Molecular structure of the title compound, showing displacement ellipsoids drawn at the 30% probability level. H atoms are presented as a small spheres of arbitrary radius.

2-Bromo-4-tert-butyl-6-[(pyridin-2-ylimino)methyl]phenol top

Crystal data top

C₁₆H₁₇BrN₂O	F(000) = 680
M_r = 333.23	D_x = 1.452 Mg m⁻³
Monoclinic, Cc	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C -2yc	Cell parameters from 3053 reflections
a = 10.0241 (11) Å	θ = 2.4–28.3°
b = 16.1355 (16) Å	µ = 2.69 mm⁻¹
c = 9.4308 (13) Å	T = 293 K
β = 92.050 (6)°	Block, red
V = 1524.4 (3) Å³	0.2 × 0.2 × 0.2 mm
Z = 4

Data collection top

Bruker SMART APEXII area-detector diffractometer	2564 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.035
Graphite monochromator	θ_max = 28.3°, θ_min = 2.4°
ω and φ scans	h = −13→13
6913 measured reflections	k = −21→21
3051 independent reflections	l = −12→12

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.033	H-atom parameters constrained
wR(F²) = 0.081	w = 1/[σ²(F_o²) + (0.0327P)²] where P = (F_o² + 2F_c²)/3
S = 0.98	(Δ/σ)_max = 0.001
3051 reflections	Δρ_max = 0.50 e Å⁻³
184 parameters	Δρ_min = −0.37 e Å⁻³
2 restraints	Absolute structure: Flack (1983), 1147 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.009 (9)

Crystal data top

C₁₆H₁₇BrN₂O	V = 1524.4 (3) Å³
M_r = 333.23	Z = 4
Monoclinic, Cc	Mo Kα radiation
a = 10.0241 (11) Å	µ = 2.69 mm⁻¹
b = 16.1355 (16) Å	T = 293 K
c = 9.4308 (13) Å	0.2 × 0.2 × 0.2 mm
β = 92.050 (6)°

Data collection top

Bruker SMART APEXII area-detector diffractometer	2564 reflections with I > 2σ(I)
6913 measured reflections	R_int = 0.035
3051 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.033	H-atom parameters constrained
wR(F²) = 0.081	Δρ_max = 0.50 e Å⁻³
S = 0.98	Δρ_min = −0.37 e Å⁻³
3051 reflections	Absolute structure: Flack (1983), 1147 Friedel pairs
184 parameters	Absolute structure parameter: 0.009 (9)
2 restraints

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
C1	0.5566 (3)	0.96379 (15)	0.4642 (4)	0.0358 (6)
C2	0.6217 (3)	1.03392 (15)	0.5239 (3)	0.0349 (6)
C3	0.5803 (3)	1.11292 (14)	0.4782 (4)	0.0391 (7)
H3	0.6233	1.1589	0.5178	0.047*
C4	0.4795 (3)	1.12589 (15)	0.3781 (4)	0.0361 (6)
C5	0.4150 (3)	1.05601 (17)	0.3224 (4)	0.0379 (7)
H5	0.3454	1.0623	0.2554	0.045*
C6	0.4536 (3)	0.97694 (16)	0.3657 (4)	0.0388 (7)
C7	0.7280 (3)	1.02509 (19)	0.6298 (4)	0.0421 (8)
H7	0.7676	1.0725	0.6684	0.051*
C8	0.8724 (4)	0.94730 (17)	0.7759 (5)	0.0423 (7)
C9	0.9091 (3)	0.8682 (2)	0.8210 (5)	0.0531 (9)
H9	0.8653	0.8219	0.7837	0.064*
C10	1.0103 (4)	0.8595 (3)	0.9207 (5)	0.0653 (11)
H10	1.0367	0.8069	0.9510	0.078*
C11	1.0721 (4)	0.9279 (3)	0.9754 (5)	0.0698 (11)
H11	1.1401	0.9235	1.0447	0.084*
C12	1.0307 (4)	1.0042 (3)	0.9248 (5)	0.0695 (13)
H12	1.0734	1.0511	0.9615	0.083*
C13	0.4388 (3)	1.2146 (2)	0.3348 (4)	0.0436 (8)
C14	0.3815 (4)	1.2584 (2)	0.4631 (5)	0.0662 (10)
H14A	0.3569	1.3140	0.4375	0.099*
H14B	0.4475	1.2596	0.5394	0.099*
H14C	0.3041	1.2289	0.4929	0.099*
C15	0.5606 (3)	1.26226 (17)	0.2862 (5)	0.0564 (9)
H15A	0.5982	1.2340	0.2074	0.085*
H15B	0.6259	1.2656	0.3629	0.085*
H15C	0.5342	1.3171	0.2576	0.085*
C16	0.3336 (4)	1.2144 (3)	0.2134 (6)	0.0654 (12)
H16A	0.3703	1.1896	0.1309	0.098*
H16B	0.3071	1.2704	0.1921	0.098*
H16C	0.2573	1.1832	0.2410	0.098*
Br1	0.36263 (5)	0.884372 (16)	0.28725 (6)	0.06324 (14)
N1	0.7694 (2)	0.95411 (16)	0.6724 (3)	0.0412 (6)
N2	0.9331 (3)	1.01500 (19)	0.8263 (4)	0.0573 (8)
O1	0.5940 (2)	0.88708 (9)	0.5015 (3)	0.0519 (7)
H1	0.5462	0.8533	0.4592	0.078*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0336 (12)	0.0318 (11)	0.0417 (18)	0.0008 (10)	−0.0011 (12)	0.0018 (12)
C2	0.0341 (12)	0.0318 (11)	0.0383 (18)	0.0021 (10)	−0.0067 (12)	0.0026 (12)
C3	0.0421 (14)	0.0292 (12)	0.0452 (19)	0.0002 (10)	−0.0085 (14)	−0.0002 (12)
C4	0.0337 (12)	0.0357 (13)	0.0387 (18)	0.0014 (10)	−0.0023 (13)	0.0025 (13)
C5	0.0330 (13)	0.0400 (14)	0.0401 (18)	−0.0020 (10)	−0.0077 (12)	0.0009 (13)
C6	0.0383 (14)	0.0352 (12)	0.0428 (19)	−0.0049 (11)	0.0003 (13)	−0.0021 (13)
C7	0.0447 (16)	0.0343 (13)	0.047 (2)	0.0019 (11)	−0.0068 (15)	−0.0023 (14)
C8	0.0405 (15)	0.0473 (13)	0.0388 (19)	0.0049 (15)	−0.0022 (13)	0.0061 (18)
C9	0.0532 (19)	0.0542 (18)	0.052 (2)	0.0096 (13)	−0.0039 (16)	0.0086 (16)
C10	0.060 (2)	0.076 (2)	0.059 (3)	0.0227 (19)	−0.003 (2)	0.026 (2)
C11	0.0523 (19)	0.101 (3)	0.055 (2)	0.011 (2)	−0.0214 (17)	0.015 (2)
C12	0.060 (2)	0.081 (3)	0.066 (3)	−0.0077 (19)	−0.024 (2)	0.010 (2)
C13	0.0484 (17)	0.0345 (15)	0.047 (2)	0.0037 (13)	−0.0061 (16)	0.0045 (14)
C14	0.076 (2)	0.0498 (18)	0.074 (3)	0.0211 (16)	0.013 (2)	0.0060 (18)
C15	0.067 (2)	0.0377 (14)	0.064 (3)	−0.0013 (13)	−0.0035 (18)	0.0117 (15)
C16	0.067 (3)	0.051 (2)	0.077 (3)	0.0112 (17)	−0.024 (2)	0.011 (2)
Br1	0.0703 (2)	0.04400 (16)	0.0735 (3)	−0.01579 (16)	−0.02473 (16)	−0.0033 (2)
N1	0.0381 (12)	0.0418 (13)	0.0431 (17)	0.0045 (10)	−0.0089 (11)	0.0036 (11)
N2	0.0525 (15)	0.0573 (16)	0.060 (2)	−0.0037 (12)	−0.0218 (14)	0.0070 (15)
O1	0.0612 (14)	0.0255 (9)	0.0679 (19)	−0.0005 (8)	−0.0146 (13)	0.0030 (9)

Geometric parameters (Å, º) top

C1—O1	1.337 (3)	C10—C11	1.359 (7)
C1—C6	1.380 (4)	C10—H10	0.9300
C1—C2	1.413 (3)	C11—C12	1.378 (6)
C2—C3	1.404 (3)	C11—H11	0.9300
C2—C7	1.441 (5)	C12—N2	1.336 (5)
C3—C4	1.373 (5)	C12—H12	0.9300
C3—H3	0.9300	C13—C16	1.529 (5)
C4—C5	1.393 (4)	C13—C15	1.527 (5)
C4—C13	1.540 (4)	C13—C14	1.531 (6)
C5—C6	1.390 (4)	C14—H14A	0.9600
C5—H5	0.9300	C14—H14B	0.9600
C6—Br1	1.887 (3)	C14—H14C	0.9600
C7—N1	1.278 (4)	C15—H15A	0.9600
C7—H7	0.9300	C15—H15B	0.9600
C8—N2	1.330 (5)	C15—H15C	0.9600
C8—C9	1.390 (4)	C16—H16A	0.9600
C8—N1	1.399 (5)	C16—H16B	0.9600
C9—C10	1.366 (6)	C16—H16C	0.9600
C9—H9	0.9300	O1—H1	0.8200

O1—C1—C6	121.0 (3)	C12—C11—H11	121.1
O1—C1—C2	121.0 (3)	N2—C12—C11	124.2 (4)
C6—C1—C2	117.9 (2)	N2—C12—H12	117.9
C3—C2—C1	118.5 (3)	C11—C12—H12	117.9
C3—C2—C7	120.4 (3)	C16—C13—C15	108.3 (3)
C1—C2—C7	121.1 (2)	C16—C13—C14	108.9 (4)
C4—C3—C2	123.5 (2)	C15—C13—C14	109.4 (3)
C4—C3—H3	118.3	C16—C13—C4	111.5 (3)
C2—C3—H3	118.3	C15—C13—C4	110.0 (3)
C3—C4—C5	117.1 (2)	C14—C13—C4	108.8 (3)
C3—C4—C13	120.4 (3)	C13—C14—H14A	109.5
C5—C4—C13	122.5 (3)	C13—C14—H14B	109.5
C6—C5—C4	120.8 (3)	H14A—C14—H14B	109.5
C6—C5—H5	119.6	C13—C14—H14C	109.5
C4—C5—H5	119.6	H14A—C14—H14C	109.5
C1—C6—C5	122.2 (3)	H14B—C14—H14C	109.5
C1—C6—Br1	118.8 (2)	C13—C15—H15A	109.5
C5—C6—Br1	119.1 (2)	C13—C15—H15B	109.5
N1—C7—C2	122.0 (3)	H15A—C15—H15B	109.5
N1—C7—H7	119.0	C13—C15—H15C	109.5
C2—C7—H7	119.0	H15A—C15—H15C	109.5
N2—C8—C9	122.1 (4)	H15B—C15—H15C	109.5
N2—C8—N1	120.1 (3)	C13—C16—H16A	109.5
C9—C8—N1	117.8 (3)	C13—C16—H16B	109.5
C10—C9—C8	119.2 (4)	H16A—C16—H16B	109.5
C10—C9—H9	120.4	C13—C16—H16C	109.5
C8—C9—H9	120.4	H16A—C16—H16C	109.5
C9—C10—C11	119.6 (4)	H16B—C16—H16C	109.5
C9—C10—H10	120.2	C7—N1—C8	120.9 (3)
C11—C10—H10	120.2	C8—N2—C12	117.1 (4)
C10—C11—C12	117.8 (4)	C1—O1—H1	109.5
C10—C11—H11	121.1

O1—C1—C2—C3	178.5 (3)	N2—C8—C9—C10	0.3 (6)
C6—C1—C2—C3	−1.2 (4)	N1—C8—C9—C10	179.3 (3)
O1—C1—C2—C7	−1.8 (4)	C8—C9—C10—C11	0.9 (6)
C6—C1—C2—C7	178.5 (3)	C9—C10—C11—C12	−1.2 (6)
C1—C2—C3—C4	−0.1 (5)	C10—C11—C12—N2	0.5 (7)
C7—C2—C3—C4	−179.8 (3)	C3—C4—C13—C16	175.1 (4)
C2—C3—C4—C5	1.1 (5)	C5—C4—C13—C16	−6.8 (5)
C2—C3—C4—C13	179.4 (3)	C3—C4—C13—C15	55.0 (5)
C3—C4—C5—C6	−1.0 (5)	C5—C4—C13—C15	−126.9 (3)
C13—C4—C5—C6	−179.1 (3)	C3—C4—C13—C14	−64.8 (4)
O1—C1—C6—C5	−178.3 (3)	C5—C4—C13—C14	113.3 (4)
C2—C1—C6—C5	1.4 (5)	C2—C7—N1—C8	−179.8 (3)
O1—C1—C6—Br1	1.6 (4)	N2—C8—N1—C7	−3.3 (5)
C2—C1—C6—Br1	−178.7 (2)	C9—C8—N1—C7	177.7 (3)
C4—C5—C6—C1	−0.3 (5)	C9—C8—N2—C12	−1.0 (6)
C4—C5—C6—Br1	179.8 (2)	N1—C8—N2—C12	−180.0 (3)
C3—C2—C7—N1	−179.1 (3)	C11—C12—N2—C8	0.6 (6)
C1—C2—C7—N1	1.3 (5)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···Br1	0.82	2.46	3.021 (3)	127
C7—H7···N2	0.93	2.38	2.723 (5)	102

Experimental details

Crystal data
Chemical formula	C₁₆H₁₇BrN₂O
M_r	333.23
Crystal system, space group	Monoclinic, Cc
Temperature (K)	293
a, b, c (Å)	10.0241 (11), 16.1355 (16), 9.4308 (13)
β (°)	92.050 (6)
V (Å³)	1524.4 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	2.69
Crystal size (mm)	0.2 × 0.2 × 0.2

Data collection
Diffractometer	Bruker SMART APEXII area-detector
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	6913, 3051, 2564
R_int	0.035
(sin θ/λ)_max (Å⁻¹)	0.668

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.033, 0.081, 0.98
No. of reflections	3051
No. of parameters	184
No. of restraints	2
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.50, −0.37
Absolute structure	Flack (1983), 1147 Friedel pairs
Absolute structure parameter	0.009 (9)

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···Br1	0.82	2.46	3.021 (3)	127
C7—H7···N2	0.93	2.38	2.723 (5)	102

Acknowledgements

The authors thank the TBI X-ray facility, CAS in Crystallography and Biophysics, University of Madras, India, for the data collection.

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