N-[2-(4-Bromo­benzo­yl)eth­yl]isopropyl­aminium chloride

Aydın, A.; Akkurt, M.; Gul, H.I.; Mete, E.; Sahin, E.

doi:10.1107/S1600536811052640

organic compounds

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ISSN: 2056-9890

Volume 68| Part 1| January 2012| Page o71

doi:10.1107/S1600536811052640

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N-[2-(4-Bromobenzoyl)ethyl]isopropylaminium chloride

Abdullah Aydın,^a ^* Mehmet Akkurt,^b Halise Inci Gul,^c Ebru Mete ^d and Ertan Sahin ^d

^aDepartment of Science Education, Faculty of Education, Kastamonu University, 37200 Kastamonu, Turkey, ^bDepartment of Physics, Faculty of Sciences, Erciyes University, 38039 Kayseri, Turkey, ^cDepartment of Pharmaceutical Chemistry, Faculty of Pharmacy, Atatürk University, 25240 Erzurum, Turkey, and ^dDepartment of Chemistry, Faculty of Sciences, Atatürk University, 25240 Erzurum, Turkey
^*Correspondence e-mail: aaydin@kastamonu.edu.tr

(Received 17 November 2011; accepted 6 December 2011; online 10 December 2011)

The crystal structure of the title compound, C₁₂H₁₇BrNO⁺·Cl⁻, is stabilized by N—H⋯Cl and C—H⋯O hydrogen bonds, forming a three-dimensional network. The interactions framework is completed by C—H⋯π contacts between a methylene group and the benzene ring of a symmetry-related molecule.

Related literature

For details of the pharmacological effects of Mannich bases and for the synthesis, see: Dimmock & Kumar (1997 ); Gul, Gul, et al. (2005 ); Gul, Sahin et al. (2005 ); Gul et al. (2007 ); Mete et al. (2011 ); Kucukoglu et al. (2011 ); Canturk et al. (2008 ); Chen et al. (1991 ); Suleyman et al. (2007 ). For bond-length data, see: Allen et al. (1987 ).

Experimental

Crystal data

C₁₂H₁₇BrNO⁺·Cl⁻
M_r = 306.62
Tetragonal, P 4₂ /n
a = 19.7122 (4) Å
c = 7.1738 (2) Å
V = 2787.53 (11) Å³
Z = 8
Mo Kα radiation
μ = 3.12 mm⁻¹
T = 294 K
0.15 × 0.13 × 0.11 mm

Data collection

Rigaku R-AXIS RAPID-S diffractometer
Absorption correction: multi-scan (Blessing, 1995 ) T_min = 0.632, T_max = 0.709
50060 measured reflections
2836 independent reflections
1617 reflections with I > 2σ(I)
R_int = 0.151

Refinement

R[F² > 2σ(F²)] = 0.076
wR(F²) = 0.181
S = 1.07
2836 reflections
153 parameters
2 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.67 e Å⁻³
Δρ_min = −0.81 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the benzene ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—HN2⋯Cl1	0.86 (4)	2.26 (4)	3.102 (4)	166 (5)
N1—HN1⋯Cl1ⁱ	0.86 (6)	2.27 (6)	3.133 (5)	177 (9)
C12—H12B⋯O1ⁱⁱ	0.96	2.60	3.378 (7)	139
C9—H9B⋯Cg1ⁱⁱⁱ	0.97	3.00	3.943 (6)	164
Symmetry codes: (i) $[-y+{\script{1\over 2}}, x-1, -z+{\script{3\over 2}}]$ ; (ii) -x+1, -y, -z+2; (iii) -x+1, -y, -z+1.

Data collection: CrystalClear (Rigaku/MSC, 2005 ); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SIR97 (Altomare et al., 1999 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811052640/bh2400sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811052640/bh2400Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811052640/bh2400Isup3.cml

checkCIF report

Comment top

Mannich bases are generally formed by the reaction between formaldehyde, a secondary amine and a compound containing reactive hydrogen atoms. On occasion, aldehydes other than formaldehyde may be employed and the secondary amine may be replaced by ammonia and primary amines. This process is known as the Mannich reaction (Dimmock & Kumar, 1997).

Mannich bases display varied biological activities such as antimicrobial (Gul, Sahin, et al., 2005), cytotoxic (Gul, Gul et al., 2005; Gul et al., 2007; Mete et al., 2011; Kucukoglu et al., 2011), anticancer (Dimmock & Kumar, 1997; Chen et al., 1991), anti-inflammatory (Suleyman et al., 2007), and DNA topoisomerase I inhibiting properties (Canturk et al., 2008).

A Mannich base having at least one hydrogen atom at the β position of amine group can undergo a deamination process to generate an α,β-unsaturated ketone moiety.

In the molecule of the tile compound (Fig. 1), the bond lengths are within normal ranges (Allen et al., 1987), as well as bond angles.

In the crystal structure, molecules are linked via intermolecular N—H···Cl and C—H···O hydrogen bonds (Table 1, Fig. 2), forming a three dimensional network. Furthermore, a C—H···π interaction (Table 1) contributes to the stabilization of the crystal packing.

Related literature top

For details of the pharmacological effects of Mannich bases and for the synthesis, see: Dimmock & Kumar (1997); Gul, Gul, et al. (2005); Gul, Sahin et al. (2005); Gul et al. (2007); Mete et al. (2011); Kucukoglu et al. (2011); Canturk et al. (2008); Chen et al. (1991); Suleyman et al. (2007). For bond-length data, see: Allen et al. (1987).

Experimental top

A mixture of the appropriate ketone (50 mmol), para-formaldehyde (50 mmol), and iso-propylamine hydrochloride (27 mmol) was heated in an oil bath at 403 K. The reaction vessel was then removed from the oil bath and when the temperature of the mixture dropped to 338 K, ethyl acetate (40–80 ml) was added. The mixture was stirred at room temperature for 24 h. and the resulting precipitates were then collected and the Mannich base (I) was passed through a column of silica gel 60 (70–230 mesh) using methanol as eluent. After evaporation of the solvent, the product was recrystallized from methanol. M.p.: 447–449 K. Yield: 38%. ¹H-NMR (CDCl₃) δ 1.49 (d, J = 6.8 Hz, 6H, CH(CH₃)₂), 3.34–3.38 (m, 3H, CH(CH₃)₂ and 2 x H-2), 3.73 (t, J = 7.3 Hz, 2H, 2 x H-3), 7.50 (d, J = 8.4 Hz, 2H, H-3'/5'), 7.76 (d, 2H, J = 8.4 Hz, H-2'/6'), 9.55 (brs, 2H, NH₂⁺). ¹³C-NMR (CDCl₃) δ 19.4 (CH(CH₃)₂), 35.3, 40.2, 51.3, 129.4, 129.8, 132.3, 134.7, 195.8 (CO); MS (EI) m/z: 254 (M - CH₃)⁺, 256 (M - CH₃ + 2)⁺, 270.2 (M + H)⁺, 272.2 (M + H + 2)⁺. IR (KBr, cm^-1): 2462 (NH₂⁺), 1684 (CO). Calcd. for C₁₂H₁₇BrClNO (306.63): C 47.00, H 5.59, N 4.57. Found: C 46.74, H 5.52, N 4.59 (Mete et al., 2011).

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2005); cell refinement: CrystalClear (Rigaku/MSC, 2005); data reduction: CrystalClear (Rigaku/MSC, 2005); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. The title compound with displacement ellipsoids for non-H atoms shown at the 30% probability level.
	Fig. 2. The packing and hydrogen bonding of the title salt viewed down the c axis. H atoms not involved in hydrogen bonds are omitted for the sake of clarity.

N-[2-(4-Bromobenzoyl)ethyl]isopropylaminium chloride top

Crystal data top

C₁₂H₁₇BrNO⁺·Cl⁻	D_x = 1.461 Mg m⁻³
M_r = 306.62	Melting point: 447 K
Tetragonal, P4₂/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 4bc	Cell parameters from 3888 reflections
a = 19.7122 (4) Å	θ = 2.9–26.4°
c = 7.1738 (2) Å	µ = 3.12 mm⁻¹
V = 2787.53 (11) Å³	T = 294 K
Z = 8	Block, white
F(000) = 1248	0.15 × 0.13 × 0.11 mm

Data collection top

Rigaku R-AXIS RAPID-S diffractometer	2836 independent reflections
Radiation source: Sealed Tube	1617 reflections with I > 2σ(I)
Graphite Monochromator monochromator	R_int = 0.151
Detector resolution: 10.0000 pixels mm^-1	θ_max = 26.4°, θ_min = 2.9°
dtprofit.ref scans	h = −24→24
Absorption correction: multi-scan (Blessing, 1995)	k = −24→24
T_min = 0.632, T_max = 0.709	l = −8→8
50060 measured reflections

Refinement top

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)] = 0.076	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.181	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	w = 1/[σ²(F_o²) + (0.0581P)² + 4.3122P] where P = (F_o² + 2F_c²)/3
2836 reflections	(Δ/σ)_max < 0.001
153 parameters	Δρ_max = 0.67 e Å⁻³
2 restraints	Δρ_min = −0.81 e Å⁻³
0 constraints

Crystal data top

C₁₂H₁₇BrNO⁺·Cl⁻	Z = 8
M_r = 306.62	Mo Kα radiation
Tetragonal, P4₂/n	µ = 3.12 mm⁻¹
a = 19.7122 (4) Å	T = 294 K
c = 7.1738 (2) Å	0.15 × 0.13 × 0.11 mm
V = 2787.53 (11) Å³

Data collection top

Rigaku R-AXIS RAPID-S diffractometer	2836 independent reflections
Absorption correction: multi-scan (Blessing, 1995)	1617 reflections with I > 2σ(I)
T_min = 0.632, T_max = 0.709	R_int = 0.151
50060 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.076	2 restraints
wR(F²) = 0.181	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	Δρ_max = 0.67 e Å⁻³
2836 reflections	Δρ_min = −0.81 e Å⁻³
153 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Br1	0.66757 (4)	0.19433 (5)	−0.04514 (15)	0.1156 (4)
O1	0.5235 (2)	0.0463 (2)	0.7192 (7)	0.0850 (17)
N1	0.6128 (2)	−0.1377 (2)	0.8767 (7)	0.0540 (17)
C1	0.6340 (3)	0.0359 (3)	0.3195 (9)	0.065 (2)
C2	0.6561 (3)	0.0740 (3)	0.1698 (10)	0.073 (3)
C3	0.6384 (3)	0.1411 (3)	0.1604 (10)	0.069 (2)
C4	0.5995 (3)	0.1707 (3)	0.2962 (10)	0.074 (3)
C5	0.5762 (3)	0.1323 (3)	0.4438 (9)	0.067 (2)
C6	0.5940 (3)	0.0644 (3)	0.4585 (8)	0.057 (2)
C7	0.5686 (3)	0.0245 (3)	0.6205 (9)	0.061 (2)
C8	0.5994 (3)	−0.0435 (3)	0.6592 (8)	0.063 (2)
C9	0.5742 (3)	−0.0744 (3)	0.8392 (9)	0.061 (2)
C10	0.5984 (3)	−0.1725 (3)	1.0610 (8)	0.0583 (19)
C11	0.6462 (3)	−0.2324 (3)	1.0768 (9)	0.070 (2)
C12	0.5251 (3)	−0.1928 (3)	1.0763 (8)	0.069 (2)
Cl1	0.75617 (8)	−0.07602 (8)	0.9322 (2)	0.0682 (6)
H1	0.64610	−0.00960	0.32750	0.0780*
HN1	0.604 (4)	−0.168 (3)	0.794 (9)	0.1390*
HN2	0.6548 (13)	−0.126 (4)	0.877 (12)	0.1390*
H2	0.68250	0.05440	0.07690	0.0870*
H4	0.58890	0.21660	0.28900	0.0890*
H5	0.54840	0.15200	0.53360	0.0800*
H8A	0.64830	−0.03880	0.66520	0.0760*
H8B	0.58880	−0.07390	0.55690	0.0760*
H9A	0.58050	−0.04270	0.94100	0.0730*
H9B	0.52610	−0.08460	0.82920	0.0730*
H10	0.60870	−0.14060	1.16200	0.0700*
H11A	0.63550	−0.26500	0.98190	0.1050*
H11B	0.64120	−0.25290	1.19730	0.1050*
H11C	0.69210	−0.21710	1.06120	0.1050*
H12A	0.51320	−0.22120	0.97260	0.1030*
H12B	0.49710	−0.15300	1.07580	0.1030*
H12C	0.51820	−0.21730	1.19040	0.1030*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0916 (6)	0.1139 (7)	0.1414 (9)	0.0018 (4)	0.0247 (5)	0.0597 (6)
O1	0.091 (3)	0.074 (3)	0.090 (3)	0.020 (2)	0.021 (3)	0.008 (3)
N1	0.055 (3)	0.049 (3)	0.058 (3)	0.002 (2)	−0.001 (2)	0.007 (2)
C1	0.061 (4)	0.055 (4)	0.080 (4)	0.009 (3)	−0.003 (3)	0.007 (3)
C2	0.067 (4)	0.067 (4)	0.084 (5)	0.003 (3)	0.006 (3)	0.011 (4)
C3	0.049 (3)	0.070 (4)	0.087 (5)	−0.006 (3)	−0.004 (3)	0.023 (4)
C4	0.075 (4)	0.056 (4)	0.090 (5)	0.002 (3)	−0.008 (4)	0.013 (4)
C5	0.072 (4)	0.051 (3)	0.077 (4)	0.005 (3)	−0.003 (3)	0.000 (3)
C6	0.062 (4)	0.050 (3)	0.060 (4)	−0.002 (3)	−0.010 (3)	0.004 (3)
C7	0.056 (4)	0.060 (4)	0.068 (4)	0.000 (3)	−0.004 (3)	−0.001 (3)
C8	0.064 (4)	0.061 (4)	0.065 (4)	0.006 (3)	0.001 (3)	0.009 (3)
C9	0.060 (4)	0.053 (3)	0.070 (4)	0.003 (3)	−0.003 (3)	0.005 (3)
C10	0.068 (4)	0.056 (3)	0.051 (3)	−0.003 (3)	−0.004 (3)	0.005 (3)
C11	0.070 (4)	0.072 (4)	0.067 (4)	0.009 (3)	−0.008 (3)	0.013 (3)
C12	0.067 (4)	0.075 (4)	0.064 (4)	−0.004 (3)	0.008 (3)	0.006 (3)
Cl1	0.0608 (9)	0.0857 (11)	0.0580 (9)	−0.0135 (7)	0.0045 (7)	−0.0045 (8)

Geometric parameters (Å, º) top

Br1—C3	1.899 (7)	C10—C11	1.515 (8)
O1—C7	1.215 (7)	C1—H1	0.9300
N1—C9	1.486 (7)	C2—H2	0.9300
N1—C10	1.516 (8)	C4—H4	0.9300
N1—HN2	0.86 (4)	C5—H5	0.9300
N1—HN1	0.86 (6)	C8—H8A	0.9700
C1—C2	1.381 (9)	C8—H8B	0.9700
C1—C6	1.390 (9)	C9—H9A	0.9700
C2—C3	1.370 (8)	C9—H9B	0.9700
C3—C4	1.370 (9)	C10—H10	0.9800
C4—C5	1.380 (9)	C11—H11A	0.9600
C5—C6	1.388 (8)	C11—H11B	0.9600
C6—C7	1.490 (9)	C11—H11C	0.9600
C7—C8	1.498 (8)	C12—H12A	0.9600
C8—C9	1.512 (9)	C12—H12B	0.9600
C10—C12	1.503 (8)	C12—H12C	0.9600

C9—N1—C10	116.2 (4)	C5—C4—H4	120.00
HN2—N1—HN1	113 (8)	C4—C5—H5	120.00
C9—N1—HN1	111 (5)	C6—C5—H5	120.00
C10—N1—HN2	107 (6)	C7—C8—H8A	109.00
C9—N1—HN2	106 (5)	C7—C8—H8B	109.00
C10—N1—HN1	105 (4)	C9—C8—H8A	109.00
C2—C1—C6	121.1 (6)	C9—C8—H8B	109.00
C1—C2—C3	118.9 (6)	H8A—C8—H8B	108.00
Br1—C3—C2	119.7 (5)	N1—C9—H9A	110.00
Br1—C3—C4	119.1 (5)	N1—C9—H9B	110.00
C2—C3—C4	121.3 (6)	C8—C9—H9A	110.00
C3—C4—C5	119.9 (6)	C8—C9—H9B	110.00
C4—C5—C6	120.2 (6)	H9A—C9—H9B	108.00
C5—C6—C7	118.9 (5)	N1—C10—H10	108.00
C1—C6—C7	122.5 (5)	C11—C10—H10	108.00
C1—C6—C5	118.6 (5)	C12—C10—H10	108.00
O1—C7—C6	120.9 (5)	C10—C11—H11A	109.00
C6—C7—C8	118.7 (5)	C10—C11—H11B	109.00
O1—C7—C8	120.3 (6)	C10—C11—H11C	109.00
C7—C8—C9	112.7 (5)	H11A—C11—H11B	110.00
N1—C9—C8	109.0 (5)	H11A—C11—H11C	110.00
N1—C10—C12	111.4 (5)	H11B—C11—H11C	110.00
C11—C10—C12	112.6 (5)	C10—C12—H12A	109.00
N1—C10—C11	107.5 (5)	C10—C12—H12B	110.00
C2—C1—H1	119.00	C10—C12—H12C	109.00
C6—C1—H1	119.00	H12A—C12—H12B	109.00
C1—C2—H2	121.00	H12A—C12—H12C	109.00
C3—C2—H2	121.00	H12B—C12—H12C	109.00
C3—C4—H4	120.00

C9—N1—C10—C11	−176.0 (5)	C3—C4—C5—C6	2.3 (9)
C9—N1—C10—C12	60.1 (6)	C4—C5—C6—C1	−1.7 (9)
C10—N1—C9—C8	174.9 (4)	C4—C5—C6—C7	179.4 (6)
C6—C1—C2—C3	0.5 (9)	C5—C6—C7—C8	−166.9 (5)
C2—C1—C6—C5	0.3 (9)	C1—C6—C7—O1	−165.4 (6)
C2—C1—C6—C7	179.2 (6)	C1—C6—C7—C8	14.2 (9)
C1—C2—C3—C4	0.1 (10)	C5—C6—C7—O1	13.5 (9)
C1—C2—C3—Br1	−179.5 (5)	O1—C7—C8—C9	−6.8 (8)
C2—C3—C4—C5	−1.4 (10)	C6—C7—C8—C9	173.6 (5)
Br1—C3—C4—C5	178.1 (5)	C7—C8—C9—N1	−173.8 (5)

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the benzene ring.

D—H···A	D—H	H···A	D···A	D—H···A
N1—HN2···Cl1	0.86 (4)	2.26 (4)	3.102 (4)	166 (5)
N1—HN1···Cl1ⁱ	0.86 (6)	2.27 (6)	3.133 (5)	177 (9)
C12—H12B···O1ⁱⁱ	0.96	2.60	3.378 (7)	139
C9—H9B···Cg1ⁱⁱⁱ	0.97	3.00	3.943 (6)	164

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

Experimental details

Crystal data
Chemical formula	C₁₂H₁₇BrNO⁺·Cl⁻
M_r	306.62
Crystal system, space group	Tetragonal, P4₂/n
Temperature (K)	294
a, c (Å)	19.7122 (4), 7.1738 (2)
V (Å³)	2787.53 (11)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	3.12
Crystal size (mm)	0.15 × 0.13 × 0.11

Data collection
Diffractometer	Rigaku R-AXIS RAPID-S diffractometer
Absorption correction	Multi-scan (Blessing, 1995)
T_min, T_max	0.632, 0.709
No. of measured, independent and observed [I > 2σ(I)] reflections	50060, 2836, 1617
R_int	0.151
(sin θ/λ)_max (Å⁻¹)	0.625

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.076, 0.181, 1.07
No. of reflections	2836
No. of parameters	153
No. of restraints	2
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.67, −0.81

Computer programs: CrystalClear (Rigaku/MSC, 2005), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the benzene ring.

D—H···A	D—H	H···A	D···A	D—H···A
N1—HN2···Cl1	0.86 (4)	2.26 (4)	3.102 (4)	166 (5)
N1—HN1···Cl1ⁱ	0.86 (6)	2.27 (6)	3.133 (5)	177 (9)
C12—H12B···O1ⁱⁱ	0.96	2.60	3.378 (7)	139
C9—H9B···Cg1ⁱⁱⁱ	0.97	3.00	3.943 (6)	164

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

Acknowledgements

The authors are indebted to the Department of Chemistry, Atatürk University, Erzurum, Turkey, for use of the X-ray diffractometer purchased under grant No. 2003/219 of the University Research Fund.

References

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