2-(4-Chloro­phenyl)-5-methyl-7,8,9,10-tetra­hydro-6H-cyclo­hepta­[e][1,3]­oxazolo­[3,2-a]­pyridin-11-ium perchlorate

The title compound, C₁₉H₁₉ClNO⁺·ClO₄^-, was synthesized and characterized by ¹H NMR and X-ray diffraction techniques.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.042
• wR factor = 0.107
• Data-to-parameter ratio = 15.9

checkCIF/PLATON results

No syntax errors found



Alert level B
REFLT01_ALERT_1_B  The number of symmetry-independent reflections cannot
            exceed the total number of reflections measured
            Number of symmetry-independent reflections =   4010
            Total number of reflections                =   3901
PLAT230_ALERT_2_B Hirshfeld Test Diff for    C11    -   C12     ..       7.90 su
PLAT230_ALERT_2_B Hirshfeld Test Diff for    C13    -   C14     ..       8.40 su

Alert level C
PLAT021_ALERT_1_C Ratio Unique / Expected Reflections too High ...       1.03
PLAT030_ALERT_1_C _diffrn_reflns_number .LE. _reflns_number_total .         ?
PLAT230_ALERT_2_C Hirshfeld Test Diff for    O4     -   C5      ..       5.13 su
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C9     -   C15     ..       5.85 su
PLAT244_ALERT_4_C Low Solvent  U(eq) as Compared to Neighbors ....        Cl2

Author Response: The perchlorate anion rotates in some extent around Cl2. So oxygen atoms have higher Ueq compared with Cl2.

PLAT431_ALERT_2_C Short Inter HL..A Contact  Cl1    ..  Cl1     ..       3.34 Ang.
PLAT432_ALERT_2_C Short Inter X...Y Contact  O21    ..  C5      ..       2.97 Ang.

   0 ALERT level A = In general: serious problem
   3 ALERT level B = Potentially serious problem
   7 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   6 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion

---

Computing details

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

2-(4–chlorophenyl)-5-methyl-7,8,9,10-tetrahydro-6H- cyclohepta[e][1,3]oxazolo[3,2-a]pyridin-11-ium perchlorate

Crystal data

C19H19ClNO^+·ClO4^−	F(000) = 856
Mr = 412.25	Dx = 1.442 Mg m^−3
Monoclinic, P21/c	Melting point: 573 K
Hall symbol: -P 2ybc	Cu Kα radiation, λ = 1.5418 Å
a = 7.894 (3) Å	Cell parameters from 25 reflections
b = 18.492 (3) Å	θ = 33–35°
c = 13.271 (2) Å	µ = 3.35 mm^−1
β = 101.46 (2)°	T = 293 K
V = 1898.6 (8) Å^3	Prism, colourless
Z = 4	0.20 × 0.20 × 0.20 mm

Data collection

Enraf–Nonius CAD-4 diffractometer	Rint = 0.004
Radiation source: fine–focus sealed tube	θmax = 75.0°, θmin = 4.2°
Graphite monochromator	h = −9→9
non–profiled ω scans	k = 0→23
4010 measured reflections	l = 0→16
3901 independent reflections	1 standard reflections every 200 reflections
3310 reflections with I > 2σ(I)	intensity decay: 4%

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.107	H-atom parameters constrained
S = 0.98	w = 1/[σ^2(Fo^2) + (0.0892P)^2] where P = (Fo^2 + 2Fc^2)/3
3901 reflections	(Δ/σ)max = 0.001
246 parameters	Δρmax = 0.19 e Å^−3
0 restraints	Δρmin = −0.21 e Å^−3

Special details

Experimental. ¹H NMR spectrum was recorded on a Bruker AMX–400.

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Cl1	0.86781 (4)	0.52453 (3)	0.07797 (3)	0.06898 (15)
O4	0.17048 (11)	0.47536 (4)	0.28891 (6)	0.0436 (2)
N1	0.01358 (12)	0.37622 (5)	0.26746 (7)	0.0390 (2)
C2	0.14658 (15)	0.36759 (7)	0.21245 (9)	0.0441 (3)
H2	0.1656	0.3275	0.1740	0.053*
C3	0.24131 (15)	0.42855 (6)	0.22603 (9)	0.0416 (3)
C5	0.03369 (14)	0.44152 (6)	0.31243 (8)	0.0395 (2)
C6	−0.07625 (17)	0.46718 (7)	0.37331 (10)	0.0465 (3)
H6	−0.0635	0.5134	0.4014	0.056*
C7	−0.20462 (16)	0.42191 (7)	0.39065 (9)	0.0461 (3)
C8	−0.22535 (15)	0.35241 (7)	0.34296 (9)	0.0463 (3)
C9	−0.11806 (15)	0.32975 (7)	0.28018 (9)	0.0427 (3)
C10	−0.3221 (2)	0.44627 (9)	0.46173 (12)	0.0631 (4)
H10A	−0.2840	0.4250	0.5284	0.095*
H10B	−0.4384	0.4312	0.4341	0.095*
H10C	−0.3181	0.4980	0.4677	0.095*
C11	−0.3639 (2)	0.30041 (8)	0.36231 (13)	0.0601 (3)
H11A	−0.4313	0.2845	0.2969	0.072*
H11B	−0.4410	0.3256	0.3989	0.072*
C12	−0.2889 (3)	0.23431 (11)	0.42463 (16)	0.0835 (6)
H12A	−0.1955	0.2500	0.4793	0.100*
H12B	−0.3779	0.2133	0.4565	0.100*
C13	−0.2212 (3)	0.17667 (11)	0.36238 (18)	0.0860 (6)
H13A	−0.1783	0.1372	0.4086	0.103*
H13B	−0.3186	0.1581	0.3128	0.103*
C14	−0.0819 (2)	0.19621 (8)	0.30499 (14)	0.0675 (4)
H14A	−0.0550	0.1540	0.2678	0.081*
H14B	0.0216	0.2092	0.3543	0.081*
C15	−0.1293 (2)	0.25860 (8)	0.22896 (11)	0.0564 (3)
H15A	−0.0523	0.2581	0.1804	0.068*
H15B	−0.2462	0.2515	0.1906	0.068*
C16	0.39450 (14)	0.45278 (7)	0.19029 (9)	0.0420 (3)
C17	0.47217 (16)	0.51882 (7)	0.22247 (10)	0.0447 (3)
H17	0.4257	0.5480	0.2672	0.054*
C18	0.61820 (18)	0.54115 (7)	0.18808 (11)	0.0524 (3)
H18	0.6709	0.5849	0.2100	0.063*
C19	0.68460 (15)	0.49772 (8)	0.12091 (9)	0.0477 (3)
C20	0.60781 (17)	0.43204 (8)	0.08811 (10)	0.0520 (3)
H20	0.6543	0.4035	0.0427	0.062*
C21	0.46330 (16)	0.40891 (7)	0.12229 (10)	0.0482 (3)
H21	0.4121	0.3648	0.1006	0.058*
Cl2	0.27549 (5)	0.181340 (18)	0.06047 (3)	0.05835 (13)
O21	0.2643 (3)	0.14812 (11)	−0.03242 (15)	0.1139 (5)
O22	0.2463 (3)	0.25404 (11)	0.04550 (16)	0.1247 (6)
O23	0.1430 (3)	0.15310 (11)	0.10492 (15)	0.1154 (6)
O24	0.4455 (3)	0.16810 (12)	0.11568 (16)	0.1191 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0431 (2)	0.1020 (3)	0.0675 (2)	−0.00954 (16)	0.02445 (16)	0.00796 (18)
O4	0.0388 (4)	0.0462 (4)	0.0498 (5)	0.0000 (3)	0.0186 (3)	−0.0045 (3)
N1	0.0341 (4)	0.0471 (5)	0.0381 (4)	0.0041 (4)	0.0127 (4)	−0.0010 (4)
C2	0.0415 (6)	0.0472 (6)	0.0484 (6)	0.0074 (5)	0.0201 (5)	0.0000 (5)
C3	0.0381 (6)	0.0459 (6)	0.0431 (6)	0.0088 (4)	0.0132 (4)	−0.0014 (4)
C5	0.0360 (5)	0.0467 (6)	0.0378 (5)	0.0071 (4)	0.0126 (4)	0.0020 (4)
C6	0.0467 (6)	0.0497 (6)	0.0479 (6)	0.0080 (5)	0.0211 (5)	0.0002 (5)
C7	0.0415 (6)	0.0552 (7)	0.0441 (6)	0.0119 (5)	0.0148 (5)	0.0040 (5)
C8	0.0367 (6)	0.0584 (7)	0.0466 (6)	0.0043 (5)	0.0150 (5)	0.0060 (5)
C9	0.0397 (6)	0.0498 (6)	0.0405 (5)	0.0005 (4)	0.0123 (4)	0.0020 (4)
C10	0.0594 (8)	0.0776 (9)	0.0626 (8)	0.0030 (7)	0.0368 (7)	−0.0104 (7)
C11	0.0546 (8)	0.0598 (8)	0.0749 (9)	−0.0028 (6)	0.0343 (7)	0.0033 (7)
C12	0.0945 (14)	0.0835 (12)	0.0861 (12)	0.0028 (10)	0.0505 (11)	0.0177 (9)
C13	0.0966 (14)	0.0739 (11)	0.0939 (14)	0.0047 (10)	0.0344 (11)	0.0064 (9)
C14	0.0807 (10)	0.0474 (7)	0.0808 (10)	0.0059 (7)	0.0317 (9)	0.0006 (7)
C15	0.0580 (8)	0.0618 (8)	0.0541 (7)	−0.0041 (6)	0.0224 (6)	−0.0060 (6)
C16	0.0322 (5)	0.0492 (6)	0.0449 (6)	0.0065 (4)	0.0084 (4)	0.0052 (5)
C17	0.0396 (6)	0.0494 (6)	0.0479 (6)	0.0053 (5)	0.0151 (5)	0.0003 (5)
C18	0.0454 (7)	0.0528 (7)	0.0611 (7)	−0.0050 (5)	0.0158 (6)	−0.0001 (6)
C19	0.0317 (5)	0.0682 (8)	0.0453 (6)	−0.0002 (5)	0.0124 (5)	0.0075 (5)
C20	0.0439 (6)	0.0650 (8)	0.0509 (7)	0.0033 (6)	0.0185 (5)	−0.0053 (6)
C21	0.0438 (6)	0.0524 (7)	0.0509 (6)	−0.0008 (5)	0.0157 (5)	−0.0051 (5)
Cl2	0.0605 (2)	0.0551 (2)	0.0608 (2)	0.00105 (13)	0.01539 (16)	−0.00297 (13)
O21	0.1156 (13)	0.1140 (13)	0.1132 (12)	0.0003 (10)	0.0259 (10)	−0.0127 (10)
O22	0.1493 (18)	0.1004 (12)	0.1267 (14)	−0.0064 (11)	0.0333 (13)	−0.0066 (10)
O23	0.1184 (14)	0.1116 (13)	0.1256 (14)	0.0025 (11)	0.0472 (11)	0.0062 (10)
O24	0.1067 (13)	0.1331 (16)	0.1135 (13)	0.0039 (10)	0.0124 (11)	0.0062 (10)

Geometric parameters (Å, º)

Cl1—C19	1.729 (1)	C12—H12A	0.9700
O4—C5	1.337 (1)	C12—H12B	0.9700
O4—C3	1.394 (1)	C13—C14	1.501 (3)
N1—C5	1.342 (1)	C13—H13A	0.9700
N1—C9	1.384 (1)	C13—H13B	0.9700
N1—C2	1.402 (1)	C14—C15	1.529 (2)
C2—C3	1.345 (2)	C14—H14A	0.9700
C2—H2	0.9300	C14—H14B	0.9700
C3—C16	1.455 (2)	C15—H15A	0.9700
C5—C6	1.382 (2)	C15—H15B	0.9700
C6—C7	1.369 (2)	C16—C17	1.3949 (18)
C6—H6	0.9300	C16—C21	1.4008 (17)
C7—C8	1.427 (2)	C17—C18	1.3844 (18)
C7—C10	1.517 (2)	C17—H17	0.9300
C8—C9	1.367 (2)	C18—C19	1.3785 (19)
C8—C11	1.516 (2)	C18—H18	0.9300
C9—C15	1.476 (2)	C19—C20	1.388 (2)
C10—H10A	0.9600	C20—C21	1.3769 (18)
C10—H10B	0.9600	C20—H20	0.9300
C10—H10C	0.9600	C21—H21	0.9300
C11—C12	1.528 (3)	Cl2—O21	1.364 (2)
C11—H11A	0.9700	Cl2—O22	1.372 (2)
C11—H11B	0.9700	Cl2—O23	1.400 (2)
C12—C13	1.510 (3)	Cl2—O24	1.417 (2)
C5—O4—C3	106.7 (1)	C14—C13—C12	118.85 (17)
C5—N1—C9	122.0 (1)	C14—C13—H13A	107.6
C5—N1—C2	107.4 (1)	C12—C13—H13A	107.6
C9—N1—C2	130.6 (1)	C14—C13—H13B	107.6
C3—C2—N1	106.8 (1)	C12—C13—H13B	107.6
C3—C2—H2	126.6	H13A—C13—H13B	107.0
N1—C2—H2	126.6	C13—C14—C15	114.09 (15)
C2—C3—O4	108.8 (1)	C13—C14—H14A	108.7
C2—C3—C16	133.7 (1)	C15—C14—H14A	108.7
O4—C3—C16	117.5 (1)	C13—C14—H14B	108.7
O4—C5—N1	110.3 (1)	C15—C14—H14B	108.7
O4—C5—C6	127.3 (1)	H14A—C14—H14B	107.6
N1—C5—C6	122.4 (1)	C9—C15—C14	112.61 (12)
C7—C6—C5	117.4 (1)	C9—C15—H15A	109.1
C7—C6—H6	121.3	C14—C15—H15A	109.1
C5—C6—H6	121.3	C9—C15—H15B	109.1
C6—C7—C8	120.0 (1)	C14—C15—H15B	109.1
C6—C7—C10	119.2 (1)	H15A—C15—H15B	107.8
C8—C7—C10	120.9 (1)	C17—C16—C21	120.08 (11)
C9—C8—C7	121.1 (1)	C17—C16—C3	120.87 (11)
C9—C8—C11	117.6 (1)	C21—C16—C3	119.05 (11)
C7—C8—C11	121.3 (1)	C18—C17—C16	120.29 (11)
C8—C9—N1	117.1 (1)	C18—C17—H17	119.9
C8—C9—C15	124.5 (1)	C16—C17—H17	119.9
N1—C9—C15	118.4 (1)	C19—C18—C17	119.20 (12)
C7—C10—H10A	109.5	C19—C18—H18	120.4
C7—C10—H10B	109.5	C17—C18—H18	120.4
H10A—C10—H10B	109.5	C18—C19—C20	120.94 (11)
C7—C10—H10C	109.5	C18—C19—Cl1	119.76 (11)
H10A—C10—H10C	109.5	C20—C19—Cl1	119.29 (10)
H10B—C10—H10C	109.5	C21—C20—C19	120.48 (12)
C8—C11—C12	112.6 (1)	C21—C20—H20	119.8
C8—C11—H11A	109.1	C19—C20—H20	119.8
C12—C11—H11A	109.1	C20—C21—C16	119.01 (12)
C8—C11—H11B	109.1	C20—C21—H21	120.5
C12—C11—H11B	109.1	C16—C21—H21	120.5
H11A—C11—H11B	107.8	O21—Cl2—O22	109.36 (12)
C13—C12—C11	114.19 (16)	O21—Cl2—O23	107.03 (12)
C13—C12—H12A	108.7	O22—Cl2—O23	107.98 (13)
C11—C12—H12A	108.7	O21—Cl2—O24	105.92 (12)
C13—C12—H12B	108.7	O22—Cl2—O24	111.02 (13)
C11—C12—H12B	108.7	O23—Cl2—O24	115.34 (13)
H12A—C12—H12B	107.6