organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

2-Bromo-2-methyl-N-(4-methyl-2-oxo-2H-chromen-7-yl)propanamide

aDepartment of Chemistry, IIT Madras, Chennai, TamilNadu, India
*Correspondence e-mail: damo@iitm.ac.in

(Received 24 June 2010; accepted 6 July 2010; online 14 July 2010)

In the title compound C14H14BrNO3, the coumarin ring system is almost planar (r.m.s. deviation = 0.008 Å) and an intra­molecular C—H⋯O inter­action generates an S(6) ring. In the crystal, mol­ecules are linked by N—H⋯O hydrogen bonds, with the C=O unit of the coumarin ring system acting as the acceptor group, generating [010] C(8) chains. The chain connectivity is reinforced by two C—H⋯O inter­actions.

Related literature

For backgound to the properties of coumarin derivatives, see: Sinkel et al. (2008[Sinkel, C., Greiner, A. & Agarwal, S. (2008). Macromolecules, 41, 1067-1069.]); Matyjaszewski et al. (2008[Matyjaszewski, K. & Mueller, L. (2008). Macromolecules, 41, 1067-1069.]); Stenzel-Rosenbaum et al. (2001[Stenzel-Rosenbaum, M., Davis, T. P., Chen, V. & Fane, A. G. (2001). J. Polym. Sci. A, 39, 2777-2783.]); Thaisrivongs et al. (1994[Thaisrivongs, S., Tomich, P. K., Watenpaugh, K. D., Chong, K.-T., Howe, W. J., Yang, C.-P., Strohbach, J. W. & Rush, B. D. (1994). J. Med. Chem. 37, 3200-3204.]). For a related structure, see: Haridharan et al. (2010[Haridharan, N., Ramkumar, V. & Dhamodharan, R. (2010). Acta Cryst. E66, o1606.])

[Scheme 1]

Experimental

Crystal data
  • C14H14BrNO3

  • Mr = 324.17

  • Triclinic, [P \overline 1]

  • a = 6.7054 (8) Å

  • b = 9.2415 (11) Å

  • c = 11.7612 (15) Å

  • α = 105.255 (5)°

  • β = 100.630 (5)°

  • γ = 93.572 (5)°

  • V = 686.33 (15) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 3.00 mm−1

  • T = 298 K

  • 0.42 × 0.20 × 0.15 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2004[Bruker (2004). APEX2, SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.366, Tmax = 0.662

  • 4624 measured reflections

  • 2511 independent reflections

  • 1716 reflections with I > 2σ(I)

  • Rint = 0.020

Refinement
  • R[F2 > 2σ(F2)] = 0.057

  • wR(F2) = 0.174

  • S = 1.09

  • 2511 reflections

  • 179 parameters

  • 1 restraint

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 1.16 e Å−3

  • Δρmin = −0.53 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C8—H8⋯O3 0.93 2.21 2.804 (6) 121
N1—H1N⋯O2i 0.91 (2) 2.12 (2) 3.016 (5) 168 (5)
C6—H6⋯O2i 0.93 2.38 3.189 (6) 145
C13—H13C⋯O2i 0.96 2.51 3.347 (8) 146
Symmetry code: (i) x, y+1, z.

Data collection: APEX2 (Bruker, 2004[Bruker (2004). APEX2, SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT-Plus (Bruker, 2004[Bruker (2004). APEX2, SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

The title compound C14 H14 Br N O3, is a monofunctional coumarin derivative, which is used as an initiator (Sinkel et al., 2008) in Atom Transfer Radical Polymerization (ATRP). We have already reported a similar ATRP initiator (Haridharan et al., 2010) with flourine containing coumarin derivative. The title compound reported here is a similiar derivative with bromo methyl propanamide and with a methyl substitution.

The synthesis of oxygen containing heterocyclic based initiators and their crystal structures are worth while to study due to their interesting properties and diverse bioactivities such as non peptidic HIV protease inhibition and tyrosine kinase inhibition (Thaisrivongs et al., 1994).

In the title compound C14 H14 Br N O3, the coumarin ring system is plannar and the Br atom in the 2-bromo-2-methyl propanamide moiety is almost perpendicular to the ring.

The torsion angle of C6—C7—N1—C11 and C8—C7—N1—C11 are -177.89 (2)° and -2.75 (2)° respectively. The crystal is stabilized by intermolecular N—H···O hydrogen bond.

Related literature top

For backgound to the properties of coumarin derivatives, see: Sinkel et al. (2008); Matyjaszewski et al. (2008); Stenzel-Rosenbaum et al. (2001); Thaisrivongs et al. (1994). For a related structure, see: Haridharan et al. (2010)

Experimental top

7-Amino-4-methylcoumarin (4 g, 0.022 moles), triethylamine (5.08 g, 0.050 moles) and THF (200 ml) were placed in a 3-neck round bottomed flask. Bromoisobutyrl bromide (11.54 g, 0.050 moles) was added slowly, using a syringe, with stirring, upon which an white precipitate of triethylammonium bromide was formed. The mixture was left to react for 6 h, with stirring. Subsequently, triethylammonium bromide, the precipitate was removed by filtration and the THF was removed by rotary evaporation. The resulting crude product was dissolved in ethyl acetate, washed with bicarbonate solution and then with water thrice followed by brine solution and dried over anhydrous sodium sulfate. The solvent was removed from the resulting solution by rotary evaporation. The product was purified by column chromatography technique using 10% ethyl acetate in hexane as the eluent to obtain pure initiator as a light yellow solid. Recrystallization of the compound from chloroform gave light yellow slabs of (I).

Refinement top

The nitrogen H atom was located in a difference Fourier map and refined isotropically. All other hydrogen atoms were fixed geometrically and allowed to ride on the parent carbon atoms, with aromatic C—H = 0.93 Å and methyl C—H = 0.96 Å. The displacement parameters were set for phenyl H atoms at Uiso(H) = 1.2Ueq(C) and methyl H atoms at Uiso(H) = 1.5Ueq(C).

Structure description top

The title compound C14 H14 Br N O3, is a monofunctional coumarin derivative, which is used as an initiator (Sinkel et al., 2008) in Atom Transfer Radical Polymerization (ATRP). We have already reported a similar ATRP initiator (Haridharan et al., 2010) with flourine containing coumarin derivative. The title compound reported here is a similiar derivative with bromo methyl propanamide and with a methyl substitution.

The synthesis of oxygen containing heterocyclic based initiators and their crystal structures are worth while to study due to their interesting properties and diverse bioactivities such as non peptidic HIV protease inhibition and tyrosine kinase inhibition (Thaisrivongs et al., 1994).

In the title compound C14 H14 Br N O3, the coumarin ring system is plannar and the Br atom in the 2-bromo-2-methyl propanamide moiety is almost perpendicular to the ring.

The torsion angle of C6—C7—N1—C11 and C8—C7—N1—C11 are -177.89 (2)° and -2.75 (2)° respectively. The crystal is stabilized by intermolecular N—H···O hydrogen bond.

For backgound to the properties of coumarin derivatives, see: Sinkel et al. (2008); Matyjaszewski et al. (2008); Stenzel-Rosenbaum et al. (2001); Thaisrivongs et al. (1994). For a related structure, see: Haridharan et al. (2010)

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus (Bruker, 2004); 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).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) with atoms represented as 30% probability ellipsoids.
[Figure 2] Fig. 2. The packing diagram for (I) showing the N—H···O interaction along the b axis.
2-Bromo-2-methyl-N-(4-methyl-2-oxo-2H-chromen-7-yl)propanamide top
Crystal data top
C14H14BrNO3Z = 2
Mr = 324.17F(000) = 328
Triclinic, P1Dx = 1.569 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 6.7054 (8) ÅCell parameters from 1785 reflections
b = 9.2415 (11) Åθ = 2.5–24.5°
c = 11.7612 (15) ŵ = 3.00 mm1
α = 105.255 (5)°T = 298 K
β = 100.630 (5)°Slab, light-yellow
γ = 93.572 (5)°0.42 × 0.20 × 0.15 mm
V = 686.33 (15) Å3
Data collection top
Bruker APEXII CCD
diffractometer
2511 independent reflections
Radiation source: fine-focus sealed tube1716 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.020
phi and ω scansθmax = 28.3°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
h = 85
Tmin = 0.366, Tmax = 0.662k = 1110
4624 measured reflectionsl = 1114
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.057Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.174H atoms treated by a mixture of independent and constrained refinement
S = 1.09 w = 1/[σ2(Fo2) + (0.1P)2 + 0.350P]
where P = (Fo2 + 2Fc2)/3
2511 reflections(Δ/σ)max < 0.001
179 parametersΔρmax = 1.16 e Å3
1 restraintΔρmin = 0.53 e Å3
Crystal data top
C14H14BrNO3γ = 93.572 (5)°
Mr = 324.17V = 686.33 (15) Å3
Triclinic, P1Z = 2
a = 6.7054 (8) ÅMo Kα radiation
b = 9.2415 (11) ŵ = 3.00 mm1
c = 11.7612 (15) ÅT = 298 K
α = 105.255 (5)°0.42 × 0.20 × 0.15 mm
β = 100.630 (5)°
Data collection top
Bruker APEXII CCD
diffractometer
2511 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
1716 reflections with I > 2σ(I)
Tmin = 0.366, Tmax = 0.662Rint = 0.020
4624 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0571 restraint
wR(F2) = 0.174H atoms treated by a mixture of independent and constrained refinement
S = 1.09Δρmax = 1.16 e Å3
2511 reflectionsΔρmin = 0.53 e Å3
179 parameters
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Br10.34908 (9)0.90419 (7)0.61854 (6)0.0714 (3)
C10.2652 (7)0.2486 (5)1.0477 (4)0.0377 (11)
C20.3283 (7)0.3307 (5)1.1731 (4)0.0388 (11)
H20.35510.27721.22990.047*
C30.3497 (6)0.4824 (5)1.2107 (4)0.0352 (10)
C40.3086 (6)0.5641 (5)1.1221 (4)0.0291 (10)
C50.3260 (7)0.7225 (5)1.1480 (4)0.0362 (11)
H50.36390.78071.22790.043*
C60.2890 (7)0.7927 (5)1.0596 (4)0.0347 (10)
H60.30420.89761.07950.042*
C70.2285 (6)0.7087 (5)0.9391 (4)0.0291 (9)
C80.2092 (6)0.5511 (4)0.9098 (4)0.0282 (9)
H80.17000.49260.83010.034*
C90.2497 (6)0.4850 (4)1.0021 (4)0.0267 (9)
C100.4152 (10)0.5641 (7)1.3424 (5)0.0616 (15)
H10A0.30630.61701.36940.092*
H10B0.53360.63491.35490.092*
H10C0.44770.49251.38720.092*
C110.1328 (7)0.7309 (5)0.7300 (4)0.0394 (11)
C120.0809 (8)0.8434 (6)0.6573 (4)0.0464 (12)
C130.0004 (12)0.9843 (7)0.7192 (6)0.0723 (18)
H13A0.11700.95730.74910.108*
H13B0.03971.04130.66290.108*
H13C0.10371.04430.78510.108*
C140.0590 (10)0.7627 (8)0.5376 (5)0.0688 (17)
H14A0.18970.73100.55090.103*
H14B0.00030.67600.49840.103*
H14C0.07570.83000.48760.103*
N10.1878 (5)0.7900 (4)0.8526 (3)0.0344 (9)
O10.2284 (4)0.3286 (3)0.9663 (3)0.0340 (7)
O20.2428 (6)0.1122 (4)1.0081 (3)0.0560 (10)
O30.1211 (7)0.5975 (4)0.6804 (3)0.0650 (12)
H1N0.196 (7)0.891 (3)0.889 (4)0.048 (14)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0746 (4)0.0678 (5)0.0796 (6)0.0004 (3)0.0157 (3)0.0365 (4)
C10.044 (2)0.024 (3)0.050 (3)0.0048 (18)0.007 (2)0.020 (2)
C20.048 (2)0.035 (3)0.039 (3)0.0044 (19)0.0067 (19)0.022 (2)
C30.041 (2)0.034 (3)0.032 (2)0.0017 (18)0.0041 (18)0.014 (2)
C40.035 (2)0.026 (2)0.029 (2)0.0043 (16)0.0071 (16)0.012 (2)
C50.049 (2)0.026 (2)0.028 (2)0.0052 (18)0.0016 (18)0.002 (2)
C60.059 (3)0.012 (2)0.030 (3)0.0029 (17)0.0056 (19)0.0035 (19)
C70.036 (2)0.024 (2)0.030 (2)0.0050 (16)0.0076 (16)0.011 (2)
C80.038 (2)0.018 (2)0.026 (2)0.0024 (16)0.0035 (16)0.0037 (19)
C90.0311 (18)0.017 (2)0.032 (2)0.0040 (14)0.0046 (16)0.0070 (19)
C100.091 (4)0.055 (4)0.037 (3)0.006 (3)0.001 (3)0.020 (3)
C110.055 (3)0.035 (3)0.031 (3)0.009 (2)0.0075 (19)0.015 (2)
C120.060 (3)0.041 (3)0.042 (3)0.008 (2)0.008 (2)0.018 (2)
C130.112 (5)0.063 (4)0.062 (4)0.045 (4)0.028 (3)0.037 (3)
C140.080 (4)0.074 (4)0.051 (4)0.003 (3)0.012 (3)0.036 (3)
N10.053 (2)0.020 (2)0.031 (2)0.0074 (15)0.0043 (16)0.0105 (18)
O10.0520 (17)0.0136 (15)0.0361 (18)0.0024 (12)0.0046 (13)0.0098 (14)
O20.088 (3)0.0186 (18)0.061 (2)0.0042 (16)0.0067 (19)0.0166 (17)
O30.129 (4)0.031 (2)0.0283 (19)0.016 (2)0.0016 (19)0.0069 (16)
Geometric parameters (Å, º) top
Br1—C122.017 (5)C8—H80.9300
C1—O21.213 (5)C9—O11.385 (5)
C1—O11.353 (6)C10—H10A0.9600
C1—C21.439 (7)C10—H10B0.9600
C2—C31.344 (6)C10—H10C0.9600
C2—H20.9300C11—O31.208 (6)
C3—C41.438 (7)C11—N11.370 (6)
C3—C101.502 (7)C11—C121.529 (7)
C4—C91.377 (6)C12—C131.503 (8)
C4—C51.407 (6)C12—C141.514 (7)
C5—C61.358 (7)C13—H13A0.9600
C5—H50.9300C13—H13B0.9600
C6—C71.395 (6)C13—H13C0.9600
C6—H60.9300C14—H14A0.9600
C7—C81.397 (6)C14—H14B0.9600
C7—N11.414 (6)C14—H14C0.9600
C8—C91.373 (6)N1—H1N0.91 (2)
O2—C1—O1116.6 (4)H10A—C10—H10B109.5
O2—C1—C2125.3 (4)C3—C10—H10C109.5
O1—C1—C2118.1 (4)H10A—C10—H10C109.5
C3—C2—C1122.1 (4)H10B—C10—H10C109.5
C3—C2—H2119.0O3—C11—N1123.0 (4)
C1—C2—H2119.0O3—C11—C12120.7 (4)
C2—C3—C4118.5 (4)N1—C11—C12116.2 (4)
C2—C3—C10120.5 (4)C13—C12—C14111.2 (5)
C4—C3—C10121.0 (4)C13—C12—C11116.9 (4)
C9—C4—C5116.0 (4)C14—C12—C11109.7 (4)
C9—C4—C3119.2 (4)C13—C12—Br1108.2 (4)
C5—C4—C3124.8 (4)C14—C12—Br1106.0 (4)
C6—C5—C4121.8 (4)C11—C12—Br1104.1 (3)
C6—C5—H5119.1C12—C13—H13A109.5
C4—C5—H5119.1C12—C13—H13B109.5
C5—C6—C7120.5 (4)H13A—C13—H13B109.5
C5—C6—H6119.7C12—C13—H13C109.5
C7—C6—H6119.7H13A—C13—H13C109.5
C6—C7—C8119.3 (4)H13B—C13—H13C109.5
C6—C7—N1117.1 (4)C12—C14—H14A109.5
C8—C7—N1123.5 (4)C12—C14—H14B109.5
C9—C8—C7118.1 (4)H14A—C14—H14B109.5
C9—C8—H8120.9C12—C14—H14C109.5
C7—C8—H8120.9H14A—C14—H14C109.5
C8—C9—C4124.2 (4)H14B—C14—H14C109.5
C8—C9—O1114.9 (3)C11—N1—C7126.8 (4)
C4—C9—O1120.9 (4)C11—N1—H1N122 (3)
C3—C10—H10A109.5C7—N1—H1N111 (3)
C3—C10—H10B109.5C1—O1—C9121.2 (3)
O2—C1—C2—C3179.9 (5)C3—C4—C9—C8179.1 (4)
O1—C1—C2—C30.5 (6)C5—C4—C9—O1179.8 (3)
C1—C2—C3—C40.2 (6)C3—C4—C9—O10.5 (6)
C1—C2—C3—C10179.8 (4)O3—C11—C12—C13150.9 (6)
C2—C3—C4—C90.3 (6)N1—C11—C12—C1327.8 (7)
C10—C3—C4—C9179.7 (4)O3—C11—C12—C1423.1 (7)
C2—C3—C4—C5179.5 (4)N1—C11—C12—C14155.6 (5)
C10—C3—C4—C50.5 (7)O3—C11—C12—Br189.9 (5)
C9—C4—C5—C60.7 (6)N1—C11—C12—Br191.4 (4)
C3—C4—C5—C6178.6 (4)O3—C11—N1—C73.3 (7)
C4—C5—C6—C71.1 (7)C12—C11—N1—C7175.3 (4)
C5—C6—C7—C81.0 (6)C6—C7—N1—C11177.9 (4)
C5—C6—C7—N1178.4 (4)C8—C7—N1—C112.8 (6)
C6—C7—C8—C90.5 (6)O2—C1—O1—C9180.0 (4)
N1—C7—C8—C9178.9 (4)C2—C1—O1—C90.3 (6)
C7—C8—C9—C40.1 (6)C8—C9—O1—C1179.4 (4)
C7—C8—C9—O1179.7 (3)C4—C9—O1—C10.2 (5)
C5—C4—C9—C80.2 (6)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8···O30.932.212.804 (6)121
N1—H1N···O2i0.91 (2)2.12 (2)3.016 (5)168 (5)
C6—H6···O2i0.932.383.189 (6)145
C13—H13C···O2i0.962.513.347 (8)146
Symmetry code: (i) x, y+1, z.

Experimental details

Crystal data
Chemical formulaC14H14BrNO3
Mr324.17
Crystal system, space groupTriclinic, P1
Temperature (K)298
a, b, c (Å)6.7054 (8), 9.2415 (11), 11.7612 (15)
α, β, γ (°)105.255 (5), 100.630 (5), 93.572 (5)
V3)686.33 (15)
Z2
Radiation typeMo Kα
µ (mm1)3.00
Crystal size (mm)0.42 × 0.20 × 0.15
Data collection
DiffractometerBruker APEXII CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2004)
Tmin, Tmax0.366, 0.662
No. of measured, independent and
observed [I > 2σ(I)] reflections
4624, 2511, 1716
Rint0.020
(sin θ/λ)max1)0.666
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.057, 0.174, 1.09
No. of reflections2511
No. of parameters179
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)1.16, 0.53

Computer programs: APEX2 (Bruker, 2004), SAINT-Plus (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8···O30.932.212.804 (6)121
N1—H1N···O2i0.91 (2)2.12 (2)3.016 (5)168 (5)
C6—H6···O2i0.932.383.189 (6)145
C13—H13C···O2i0.962.513.347 (8)146
Symmetry code: (i) x, y+1, z.
 

Acknowledgements

The authors acknowledge the Department of Chemistry, IIT Madras, for the X-ray data collection.

References

First citationBruker (2004). APEX2, SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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