5-(4-Chloro­phen­yl)-6-isopropyl-5,6-dihydro-4H-pyrrolo­[3,4-c]isoxazole

Ha, K.; Lim, H.S.; Kim, H.J.

doi:10.1107/S1600536810034872

organic compounds

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ISSN: 2056-9890

Volume 66| Part 10| October 2010| Page o2483

doi:10.1107/S1600536810034872

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5-(4-Chlorophenyl)-6-isopropyl-5,6-dihydro-4H-pyrrolo[3,4-c]isoxazole

Kwang Ha,^a Hyun Sub Lim ^a and Hyung Jin Kim ^a ^*

^aSchool of Applied Chemical Engineering, Chonnam National University, Gwangju 500-757, Republic of Korea
^*Correspondence e-mail: hyungkim@chonnam.ac.kr

(Received 25 August 2010; accepted 30 August 2010; online 4 September 2010)

The title compound, C₁₄H₁₅ClN₂O, contains an eight-membered 5,5-fused bicycle with two substituents. The dihedral angle between the nearly planar eight-membered ring [maximum deviation = 0.033 (2) Å] and the benzene ring is 25.0 (1)°. In the crystal structure, molecules are stacked in columns along the b axis and C—H⋯π interactions are observed between the columns.

Related literature

For the synthesis of the title compound, see: Kim & Lee (1994 ). For the biological activity of isoxazoles, see: Boyd (1991 ); Kim et al. (1994 , 1997 , 1999 ); Lang & Lin (1984 ); Sutharchanadevi & Murugan (1996 ).

Experimental

Crystal data

C₁₄H₁₅ClN₂O
M_r = 262.73
Monoclinic, P 2₁ /c
a = 15.0037 (9) Å
b = 6.2364 (4) Å
c = 15.5801 (9) Å
β = 117.238 (1)°
V = 1296.16 (14) Å³
Z = 4
Mo Kα radiation
μ = 0.28 mm⁻¹
T = 200 K
0.35 × 0.28 × 0.12 mm

Data collection

Bruker SMART 1000 CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2000 ) T_min = 0.861, T_max = 0.966
9224 measured reflections
3211 independent reflections
1907 reflections with I > 2σ(I)
R_int = 0.043

Refinement

R[F² > 2σ(F²)] = 0.044
wR(F²) = 0.117
S = 1.07
3211 reflections
165 parameters
H-atom parameters constrained
Δρ_max = 0.36 e Å⁻³
Δρ_min = −0.44 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C1–C6 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C5—H5⋯Cg1ⁱ	0.95	2.65	3.405 (3)	136
C9—H9⋯Cg1ⁱⁱ	0.95	2.62	3.392 (3)	138
Symmetry codes: (i) $[-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (ii) $[x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); 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 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810034872/is2594sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810034872/is2594Isup2.hkl

checkCIF report

Comment top

Isoxazole derivatives bearing various substituents are known to have diverse biological activities in pharmaceutical and agricultural areas (Lang & Lin, 1984; Boyd, 1991). Dihydropyrrolo[3,4-c]isoxazole, a fused bicyclic isoxazole, is interesting to develop a new lead compound as a plant fungicide because bicyclic isoxazoles such as dihydrofuro[3,4-c]isoxazole and dihydropyrano[3,4-c]isoxazole derivatives particularly have fungicidal activities against some plant pathogens (Kim et al., 1994, 1997, 1999). The title compound was prepared by the known method (Kim & Lee, 1994) with a minor modification.

The title compound, C₁₄H₁₅ClN₂O, is an 8-membered 5,5-fused bicycle with two substituents (Fig. 1). The dihedral angle between the nearly planar 8-membered ring [maximum deviation of 0.033 (2) Å for C7] and the benzene ring [maximum deviation of 0.023 (2) Å for C1] is 25.0 (1)°. In the crystal structure, the molecules are stacked in columns along the b axis (Fig. 2), and display C—H···Cg1 (the centroid of ring C1–C6) interactions (Table 1).

Related literature top

For the synthesis of the title compound, see: Kim & Lee (1994). For the biological activity of isoxazoles, see: Boyd (1991); Kim et al. (1994, 1997, 1999); Lang & Lin (1984); Sutharchanadevi & Murugan (1996).

Experimental top

A mixture of 3-methyl-1-nitrobutan-2-yl acetate (1.23 g, 7 mmol), 4-chloro-N-(prop-2-ynyl)aniline (3.48 g, 21 mmol) and K₂CO₃ (1.16 g, 8.4 mmol) in THF (20 ml) was stirred for 12 h at 25 °C. The mixture was concentrated in vacuo and column chromatographed (SiO₂) by eluting with a mixture of n-hexane/EtOAc (5:1) to afford 4-chloro-N-(3-methyl-1-nitrobutan-2-yl)-N-(prop-2-ynyl)aniline (0.49 g, 25%). The title compound was prepared by the intramolecular nitrile oxide-alkyne cycloaddition of 4-chloro-N-(3-methyl-1-nitrobutan-2-yl)-N-(prop-2-ynyl)aniline in the presence of 4-chlorophenylisocyanate and triethylamine (Kim & Lee, 1994). Crystals suitable for X-ray analysis were obtained by slow evaporation from an n-hexane/CHCl₃ solution.

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The structure of the title compound, with displacement ellipsoids drawn at the 50% probability level for non-H atoms.
	Fig. 2. View of the unit-cell contents of the title compound.

5-(4-Chlorophenyl)-6-isopropyl-5,6-dihydro-4H- pyrrolo[3,4-c]isoxazole top

Crystal data top

C₁₄H₁₅ClN₂O	F(000) = 552
M_r = 262.73	D_x = 1.346 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2659 reflections
a = 15.0037 (9) Å	θ = 2.6–27.1°
b = 6.2364 (4) Å	µ = 0.28 mm⁻¹
c = 15.5801 (9) Å	T = 200 K
β = 117.238 (1)°	Stick, pale yellow
V = 1296.16 (14) Å³	0.35 × 0.28 × 0.12 mm
Z = 4

Data collection top

Bruker SMART 1000 CCD diffractometer	3211 independent reflections
Radiation source: fine-focus sealed tube	1907 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.043
ϕ and ω scans	θ_max = 28.3°, θ_min = 2.6°
Absorption correction: multi-scan (SADABS; Bruker, 2000)	h = −19→20
T_min = 0.861, T_max = 0.966	k = −8→8
9224 measured reflections	l = −18→20

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)] = 0.044	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.117	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.0311P)² + 0.6269P] where P = (F_o² + 2F_c²)/3
3211 reflections	(Δ/σ)_max = 0.001
165 parameters	Δρ_max = 0.36 e Å⁻³
0 restraints	Δρ_min = −0.44 e Å⁻³

Crystal data top

C₁₄H₁₅ClN₂O	V = 1296.16 (14) Å³
M_r = 262.73	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 15.0037 (9) Å	µ = 0.28 mm⁻¹
b = 6.2364 (4) Å	T = 200 K
c = 15.5801 (9) Å	0.35 × 0.28 × 0.12 mm
β = 117.238 (1)°

Data collection top

Bruker SMART 1000 CCD diffractometer	3211 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2000)	1907 reflections with I > 2σ(I)
T_min = 0.861, T_max = 0.966	R_int = 0.043
9224 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.044	0 restraints
wR(F²) = 0.117	H-atom parameters constrained
S = 1.07	Δρ_max = 0.36 e Å⁻³
3211 reflections	Δρ_min = −0.44 e Å⁻³
165 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

	x	y	z	U_iso*/U_eq
Cl1	0.53029 (5)	0.72970 (11)	0.07428 (5)	0.0460 (2)
O1	0.17957 (13)	1.1528 (3)	0.45555 (12)	0.0468 (5)
N1	0.25711 (13)	0.8986 (3)	0.24578 (13)	0.0292 (4)
N2	0.17208 (15)	1.2612 (3)	0.37156 (14)	0.0400 (5)
C1	0.31613 (16)	0.8552 (4)	0.20076 (15)	0.0284 (5)
C2	0.32447 (17)	1.0003 (4)	0.13595 (16)	0.0317 (5)
H2	0.2857	1.1280	0.1193	0.038*
C3	0.38835 (17)	0.9599 (4)	0.09593 (16)	0.0341 (5)
H3	0.3940	1.0608	0.0530	0.041*
C4	0.44355 (17)	0.7739 (4)	0.11838 (16)	0.0327 (5)
C5	0.43342 (16)	0.6228 (4)	0.17806 (16)	0.0333 (5)
H5	0.4696	0.4918	0.1911	0.040*
C6	0.37017 (16)	0.6630 (4)	0.21896 (16)	0.0316 (5)
H6	0.3634	0.5586	0.2600	0.038*
C7	0.27190 (18)	0.7731 (4)	0.33222 (17)	0.0341 (5)
H7A	0.3437	0.7411	0.3738	0.041*
H7B	0.2335	0.6372	0.3140	0.041*
C8	0.23192 (17)	0.9227 (4)	0.38036 (16)	0.0322 (5)
C9	0.21539 (18)	0.9522 (4)	0.45747 (17)	0.0412 (6)
H9	0.2271	0.8481	0.5060	0.049*
C10	0.20329 (16)	1.1175 (4)	0.33080 (16)	0.0298 (5)
C11	0.21313 (16)	1.1144 (4)	0.23924 (15)	0.0279 (5)
H11	0.2625	1.2261	0.2426	0.034*
C12	0.11400 (17)	1.1478 (4)	0.14745 (16)	0.0325 (5)
H12	0.1255	1.1103	0.0909	0.039*
C13	0.0833 (2)	1.3827 (4)	0.13769 (19)	0.0464 (7)
H13A	0.0713	1.4239	0.1922	0.070*
H13B	0.0218	1.4036	0.0772	0.070*
H13C	0.1369	1.4716	0.1373	0.070*
C14	0.03096 (18)	1.0035 (4)	0.14450 (19)	0.0488 (7)
H14A	0.0132	1.0470	0.1951	0.073*
H14B	0.0542	0.8544	0.1551	0.073*
H14C	−0.0280	1.0161	0.0813	0.073*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0449 (4)	0.0560 (4)	0.0462 (4)	0.0075 (3)	0.0287 (3)	−0.0022 (3)
O1	0.0517 (11)	0.0585 (12)	0.0343 (10)	0.0084 (9)	0.0233 (9)	−0.0015 (9)
N1	0.0326 (10)	0.0275 (10)	0.0298 (10)	0.0036 (8)	0.0164 (8)	0.0050 (8)
N2	0.0474 (12)	0.0423 (12)	0.0348 (11)	0.0057 (10)	0.0226 (10)	0.0010 (10)
C1	0.0285 (12)	0.0294 (12)	0.0256 (12)	−0.0007 (10)	0.0109 (9)	−0.0007 (9)
C2	0.0340 (13)	0.0306 (12)	0.0314 (13)	0.0048 (10)	0.0158 (10)	0.0041 (10)
C3	0.0370 (13)	0.0362 (14)	0.0310 (13)	−0.0029 (11)	0.0172 (11)	0.0018 (10)
C4	0.0322 (12)	0.0364 (13)	0.0315 (13)	0.0016 (11)	0.0163 (10)	−0.0042 (10)
C5	0.0312 (12)	0.0306 (13)	0.0340 (13)	0.0033 (10)	0.0115 (10)	−0.0008 (10)
C6	0.0300 (12)	0.0314 (12)	0.0308 (12)	0.0003 (10)	0.0117 (10)	0.0027 (10)
C7	0.0414 (13)	0.0312 (13)	0.0331 (13)	0.0030 (11)	0.0199 (11)	0.0064 (10)
C8	0.0317 (12)	0.0369 (13)	0.0291 (12)	−0.0003 (11)	0.0148 (10)	0.0034 (10)
C9	0.0400 (14)	0.0509 (16)	0.0330 (14)	0.0066 (12)	0.0171 (11)	0.0067 (12)
C10	0.0264 (11)	0.0332 (13)	0.0294 (12)	−0.0006 (10)	0.0124 (10)	−0.0002 (10)
C11	0.0275 (11)	0.0290 (12)	0.0286 (12)	−0.0002 (10)	0.0139 (9)	0.0017 (9)
C12	0.0322 (13)	0.0359 (13)	0.0283 (12)	0.0036 (10)	0.0128 (10)	0.0030 (10)
C13	0.0456 (15)	0.0455 (16)	0.0449 (16)	0.0111 (13)	0.0180 (13)	0.0129 (13)
C14	0.0350 (14)	0.0522 (17)	0.0492 (16)	−0.0046 (13)	0.0106 (12)	0.0032 (13)

Geometric parameters (Å, º) top

Cl1—C4	1.749 (2)	C7—H7A	0.9900
O1—C9	1.356 (3)	C7—H7B	0.9900
O1—N2	1.431 (2)	C8—C9	1.346 (3)
N1—C1	1.385 (3)	C8—C10	1.398 (3)
N1—C11	1.482 (3)	C9—H9	0.9500
N1—C7	1.484 (3)	C10—C11	1.500 (3)
N2—C10	1.303 (3)	C11—C12	1.534 (3)
C1—C6	1.401 (3)	C11—H11	1.0000
C1—C2	1.403 (3)	C12—C14	1.521 (3)
C2—C3	1.385 (3)	C12—C13	1.522 (3)
C2—H2	0.9500	C12—H12	1.0000
C3—C4	1.374 (3)	C13—H13A	0.9800
C3—H3	0.9500	C13—H13B	0.9800
C4—C5	1.380 (3)	C13—H13C	0.9800
C5—C6	1.387 (3)	C14—H14A	0.9800
C5—H5	0.9500	C14—H14B	0.9800
C6—H6	0.9500	C14—H14C	0.9800
C7—C8	1.485 (3)

C9—O1—N2	108.68 (17)	C10—C8—C7	111.13 (19)
C1—N1—C11	120.72 (17)	C8—C9—O1	109.8 (2)
C1—N1—C7	119.44 (18)	C8—C9—H9	125.1
C11—N1—C7	114.75 (16)	O1—C9—H9	125.1
C10—N2—O1	103.03 (18)	N2—C10—C8	114.6 (2)
N1—C1—C6	120.6 (2)	N2—C10—C11	133.3 (2)
N1—C1—C2	121.8 (2)	C8—C10—C11	112.02 (19)
C6—C1—C2	117.59 (19)	N1—C11—C10	100.43 (17)
C3—C2—C1	121.0 (2)	N1—C11—C12	113.51 (18)
C3—C2—H2	119.5	C10—C11—C12	114.16 (17)
C1—C2—H2	119.5	N1—C11—H11	109.5
C4—C3—C2	120.0 (2)	C10—C11—H11	109.5
C4—C3—H3	120.0	C12—C11—H11	109.5
C2—C3—H3	120.0	C14—C12—C13	111.1 (2)
C3—C4—C5	120.6 (2)	C14—C12—C11	112.28 (19)
C3—C4—Cl1	120.21 (18)	C13—C12—C11	110.13 (19)
C5—C4—Cl1	119.21 (18)	C14—C12—H12	107.7
C4—C5—C6	119.7 (2)	C13—C12—H12	107.7
C4—C5—H5	120.1	C11—C12—H12	107.7
C6—C5—H5	120.1	C12—C13—H13A	109.5
C5—C6—C1	121.0 (2)	C12—C13—H13B	109.5
C5—C6—H6	119.5	H13A—C13—H13B	109.5
C1—C6—H6	119.5	C12—C13—H13C	109.5
N1—C7—C8	101.51 (17)	H13A—C13—H13C	109.5
N1—C7—H7A	111.5	H13B—C13—H13C	109.5
C8—C7—H7A	111.5	C12—C14—H14A	109.5
N1—C7—H7B	111.5	C12—C14—H14B	109.5
C8—C7—H7B	111.5	H14A—C14—H14B	109.5
H7A—C7—H7B	109.3	C12—C14—H14C	109.5
C9—C8—C10	103.8 (2)	H14A—C14—H14C	109.5
C9—C8—C7	145.0 (2)	H14B—C14—H14C	109.5

C9—O1—N2—C10	0.3 (2)	C7—C8—C9—O1	175.2 (3)
C11—N1—C1—C6	170.09 (19)	N2—O1—C9—C8	0.1 (3)
C7—N1—C1—C6	16.6 (3)	O1—N2—C10—C8	−0.5 (3)
C11—N1—C1—C2	−9.7 (3)	O1—N2—C10—C11	177.8 (2)
C7—N1—C1—C2	−163.2 (2)	C9—C8—C10—N2	0.6 (3)
N1—C1—C2—C3	176.2 (2)	C7—C8—C10—N2	−176.7 (2)
C6—C1—C2—C3	−3.7 (3)	C9—C8—C10—C11	−178.10 (19)
C1—C2—C3—C4	1.0 (3)	C7—C8—C10—C11	4.6 (3)
C2—C3—C4—C5	2.2 (3)	C1—N1—C11—C10	−153.36 (19)
C2—C3—C4—Cl1	−175.91 (18)	C7—N1—C11—C10	1.3 (2)
C3—C4—C5—C6	−2.7 (3)	C1—N1—C11—C12	84.4 (2)
Cl1—C4—C5—C6	175.43 (17)	C7—N1—C11—C12	−121.0 (2)
C4—C5—C6—C1	0.0 (3)	N2—C10—C11—N1	178.2 (2)
N1—C1—C6—C5	−176.7 (2)	C8—C10—C11—N1	−3.5 (2)
C2—C1—C6—C5	3.2 (3)	N2—C10—C11—C12	−60.0 (3)
C1—N1—C7—C8	156.14 (19)	C8—C10—C11—C12	118.3 (2)
C11—N1—C7—C8	1.2 (2)	N1—C11—C12—C14	65.4 (2)
N1—C7—C8—C9	−178.9 (3)	C10—C11—C12—C14	−48.9 (3)
N1—C7—C8—C10	−3.4 (2)	N1—C11—C12—C13	−170.28 (18)
C10—C8—C9—O1	−0.4 (3)	C10—C11—C12—C13	75.4 (2)

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C1–C6 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5···Cg1ⁱ	0.95	2.65	3.405 (3)	136
C9—H9···Cg1ⁱⁱ	0.95	2.62	3.392 (3)	138

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

Experimental details

Crystal data
Chemical formula	C₁₄H₁₅ClN₂O
M_r	262.73
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	200
a, b, c (Å)	15.0037 (9), 6.2364 (4), 15.5801 (9)
β (°)	117.238 (1)
V (Å³)	1296.16 (14)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.28
Crystal size (mm)	0.35 × 0.28 × 0.12

Data collection
Diffractometer	Bruker SMART 1000 CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2000)
T_min, T_max	0.861, 0.966
No. of measured, independent and observed [I > 2σ(I)] reflections	9224, 3211, 1907
R_int	0.043
(sin θ/λ)_max (Å⁻¹)	0.667

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.044, 0.117, 1.07
No. of reflections	3211
No. of parameters	165
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.36, −0.44

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C1–C6 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5···Cg1ⁱ	0.95	2.65	3.405 (3)	136
C9—H9···Cg1ⁱⁱ	0.95	2.62	3.392 (3)	138

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

Acknowledgements

This study was supported by financially Chonnam National University (2008).

References

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Volume 66| Part 10| October 2010| Page o2483

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