5,6,7,8-Tetra-hydro-quinoline 1-oxide hemihydrate.

In the title compound, C(9)H(11)NO·0.5H(2)O, the asymmetric unit contains two similar mol-ecules of 5,6,7,8-tetra-hydro-quinoline 1-oxide and one water mol-ecule. The water mol-ecule links the two O atoms of both independent N-oxides into dimers via O-H⋯O hydrogen bonds, forming a three-dimensional network along [101], which is additionally stabilized by weak C-H⋯O inter-molecular inter-actions. In each mol-ecule, the saturated six-membered rings exist in a conformation inter-mediate between a half-chair and sofa.

Related literature

For background to the chemistry of the title compound and its applications, see: Coperet et al. (1998 ▶); Li (2005 ▶); Kaiser et al. (2006 ▶); Kaczorowski et al. (2009 ▶). For the synthesis, see: Jacobs et al. (2000 ▶); Barbay et al. (2008 ▶). For the biological activity of 5,6,7,8-tetra­hydro­quinoline derivatives, see: Calhoun et al. (1995 ▶); Abd El-Salam et al. (2009 ▶). For a related structure, see: HXTHQO (CSD, November 2009 release). For structure inter­pretation tools, see: Duax & Norton (1975 ▶); Allen et al. (1987 ▶); Allen (2002 ▶); Bruno et al. (2002 ▶).

Experimental

Crystal data

C9H11NO·0.5H2O

M = 158.20

Orthorhombic,

a = 14.725 (4) Å

b = 14.464 (4) Å

c = 15.474 (3) Å

V = 3295.7 (14) Å3

Z = 16

Cu Kα radiation

μ = 0.70 mm−1

T = 293 K

0.28 × 0.26 × 0.21 mm

Data collection

Bruker SMART APEXII CCD diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2005 ▶) T min = 0.832, T max = 0.873

11258 measured reflections

2727 independent reflections

1989 reflections with I > 2σ(I)

R int = 0.053

Refinement

R[F 2 > 2σ(F 2)] = 0.051

wR(F 2) = 0.205

S = 1.39

2727 reflections

215 parameters

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.44 e Å−3

Δρmin = −0.24 e Å−3

Data collection: APEX2 (Bruker, 2005 ▶); cell refinement: SAINT (Bruker, 2005 ▶); 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 for Windows (Farrugia, 1997 ▶); software used to prepare material for publication: SHELXL97 and WinGX (Farrugia, 1999 ▶).

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810008779/jj2025sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810008779/jj2025Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C9H11NO·0.5H2O	F(000) = 1360
Mr = 158.20	Dx = 1.275 Mg m−3
Orthorhombic, Pbca	Cu Kα radiation, λ = 1.54178 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 3676 reflections
a = 14.725 (4) Å	θ = 5.7–66.9°
b = 14.464 (4) Å	µ = 0.70 mm−1
c = 15.474 (3) Å	T = 293 K
V = 3295.7 (14) Å3	Block, colourless
Z = 16	0.28 × 0.26 × 0.21 mm

Bruker SMART APEXII CCD diffractometer	2727 independent reflections
Radiation source: fine-focus sealed tube	1989 reflections with I > 2σ(I)
graphite	Rint = 0.053
φ and ω scans	θmax = 65.4°, θmin = 5.2°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −17→16
Tmin = 0.832, Tmax = 0.873	k = −16→17
11258 measured reflections	l = −18→10

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)] = 0.051	H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.205	w = 1/[σ2(Fo2) + (0.1P)2] where P = (Fo2 + 2Fc2)/3
S = 1.39	(Δ/σ)max < 0.001
2727 reflections	Δρmax = 0.44 e Å−3
215 parameters	Δρmin = −0.24 e Å−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0014 (4)

Experimental. 1H MNR (400 MHz, CDCl3) δ: 8.13 (d, 1H, J = 6.0 Hz), 7.04–6.99 (m, 2H), 2.93 (t, 2H, J = 6.4 Hz), 2.75 (t, 2H, J = 6.4 Hz), 2.40 (br s, 1H), 1.92–1.85 (m, 2H), 1,78–1.72 (m, 2H); 13C MNR (100 MHz, CDCl3) δ: 148.8, 136.9, 136.4, 126.6, 121.9, 28.6, 24.6, 21.8, 21.6; IR (KBr, ν, cm-1): 3368 (s, OH), 3312 (s, OH), 3076 (m), 3050 (m), 3009 (m), 2935 (s), 2871 (m), 2837 (m), 2498 (w), 2410 (w), 2151 (w), 1970 (w), 1686 (m, NO), 1596 (m), 1482 (m), 1449 (s), 1334 (m), 1253 (s), 1232 (s), 1211 (s), 1194 (s), 1155 (m), 1089 (m), 1074 (s), 1041 (m), 971 (s), 897 (m), 865 (w), 830 (m), 797 (s), 701 (m), 676 (m).

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 > 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.

	x	y	z	Uiso*/Ueq
O1A	0.11925 (15)	0.33158 (10)	0.13008 (9)	0.0703 (6)
N1A	0.13994 (15)	0.41708 (12)	0.11018 (11)	0.0502 (6)
C2A	0.16947 (18)	0.47498 (16)	0.17206 (15)	0.0581 (7)
H2A	0.1737	0.4547	0.2290	0.087*
C3A	0.1930 (2)	0.56261 (17)	0.15166 (17)	0.0666 (8)
H3A	0.2143	0.6025	0.1942	0.100*
C4A	0.1853 (2)	0.59244 (16)	0.06758 (18)	0.0669 (8)
H4A	0.2018	0.6527	0.0536	0.100*
C5A	0.1449 (2)	0.56465 (16)	−0.08980 (17)	0.0686 (8)
H51A	0.0900	0.6010	−0.0964	0.103*
H52A	0.1961	0.6041	−0.1041	0.103*
C6A	0.1422 (2)	0.4849 (2)	−0.15194 (16)	0.0774 (9)
H61A	0.1268	0.5075	−0.2091	0.116*
H62A	0.2018	0.4566	−0.1551	0.116*
C7A	0.0749 (2)	0.41457 (18)	−0.12508 (14)	0.0673 (8)
H71A	0.0741	0.3649	−0.1672	0.101*
H72A	0.0149	0.4424	−0.1242	0.101*
C8A	0.09560 (19)	0.37485 (14)	−0.03650 (13)	0.0534 (7)
H81A	0.0408	0.3472	−0.0132	0.080*
H82A	0.1405	0.3262	−0.0426	0.080*
C9A	0.13012 (16)	0.44502 (14)	0.02589 (12)	0.0455 (6)
C10A	0.15331 (17)	0.53397 (15)	0.00343 (15)	0.0520 (6)
O1B	0.13846 (14)	0.36329 (13)	0.38241 (10)	0.0701 (6)
N1B	0.05059 (15)	0.35441 (11)	0.39183 (10)	0.0489 (6)
C2B	−0.0012 (2)	0.33685 (15)	0.32153 (14)	0.0571 (7)
H2B	0.0258	0.3314	0.2674	0.086*
C3B	−0.0921 (2)	0.32725 (16)	0.32982 (17)	0.0647 (8)
H3B	−0.1277	0.3148	0.2815	0.097*
C4B	−0.1320 (2)	0.33585 (16)	0.40978 (19)	0.0658 (7)
H4B	−0.1946	0.3297	0.4153	0.099*
C5B	−0.1198 (3)	0.3615 (2)	0.57197 (19)	0.0843 (11)
H51B	−0.1695	0.3179	0.5776	0.126*
H52B	−0.1441	0.4232	0.5800	0.126*
C6B	−0.0486 (3)	0.3418 (2)	0.64194 (17)	0.0941 (12)
H61B	−0.0747	0.3538	0.6984	0.141*
H62B	−0.0315	0.2771	0.6397	0.141*
C7B	0.0323 (3)	0.3992 (2)	0.63022 (15)	0.0853 (11)
H71B	0.0747	0.3870	0.6768	0.128*
H72B	0.0151	0.4638	0.6331	0.128*
C8B	0.0784 (2)	0.38036 (16)	0.54433 (14)	0.0591 (7)
H81B	0.1162	0.4329	0.5295	0.089*
H82B	0.1177	0.3270	0.5505	0.089*
C9B	0.01368 (19)	0.36319 (13)	0.47254 (13)	0.0475 (6)
C10B	−0.0792 (2)	0.35369 (15)	0.48235 (15)	0.0569 (7)
O2	0.21964 (17)	0.24427 (13)	0.26255 (13)	0.0781 (7)
H21	0.188 (2)	0.269 (2)	0.213 (2)	0.117*
H22	0.195 (2)	0.280 (2)	0.308 (2)	0.117*

	U11	U22	U33	U12	U13	U23
O1A	0.1126 (19)	0.0511 (9)	0.0473 (9)	−0.0176 (9)	−0.0026 (9)	0.0080 (7)
N1A	0.0606 (16)	0.0485 (10)	0.0415 (9)	−0.0037 (8)	0.0024 (8)	−0.0043 (8)
C2A	0.0615 (18)	0.0618 (14)	0.0510 (11)	−0.0026 (12)	−0.0041 (11)	−0.0143 (11)
C3A	0.067 (2)	0.0616 (14)	0.0708 (15)	−0.0049 (12)	−0.0088 (14)	−0.0202 (12)
C4A	0.070 (2)	0.0476 (12)	0.0833 (17)	−0.0082 (12)	0.0021 (15)	−0.0046 (12)
C5A	0.079 (2)	0.0593 (14)	0.0676 (14)	−0.0017 (13)	0.0070 (14)	0.0177 (12)
C6A	0.099 (3)	0.0823 (18)	0.0509 (12)	0.0069 (16)	0.0040 (14)	0.0130 (13)
C7A	0.086 (3)	0.0698 (16)	0.0463 (12)	0.0007 (14)	−0.0053 (12)	−0.0003 (11)
C8A	0.069 (2)	0.0491 (12)	0.0426 (11)	−0.0037 (10)	0.0005 (11)	−0.0051 (9)
C9A	0.0486 (16)	0.0471 (11)	0.0408 (10)	0.0002 (9)	0.0054 (10)	−0.0019 (9)
C10A	0.0497 (17)	0.0473 (12)	0.0590 (12)	−0.0006 (9)	0.0060 (11)	0.0004 (11)
O1B	0.0602 (16)	0.0916 (13)	0.0584 (10)	−0.0088 (10)	0.0101 (9)	−0.0125 (9)
N1B	0.0553 (16)	0.0495 (10)	0.0418 (9)	−0.0027 (8)	0.0034 (9)	−0.0025 (8)
C2B	0.071 (2)	0.0567 (13)	0.0439 (11)	−0.0008 (12)	−0.0046 (12)	−0.0036 (10)
C3B	0.074 (2)	0.0562 (14)	0.0638 (15)	−0.0020 (12)	−0.0162 (14)	0.0025 (11)
C4B	0.0531 (19)	0.0587 (14)	0.0855 (18)	0.0083 (12)	0.0009 (15)	0.0121 (13)
C5B	0.089 (3)	0.0870 (19)	0.0769 (18)	0.0294 (17)	0.0379 (18)	0.0192 (15)
C6B	0.142 (4)	0.086 (2)	0.0537 (15)	0.026 (2)	0.0270 (18)	0.0116 (14)
C7B	0.136 (4)	0.0739 (17)	0.0454 (13)	0.0120 (19)	0.0020 (16)	−0.0034 (13)
C8B	0.081 (2)	0.0520 (12)	0.0446 (11)	0.0045 (11)	−0.0058 (12)	−0.0046 (10)
C9B	0.0632 (19)	0.0377 (10)	0.0416 (11)	0.0064 (9)	0.0042 (10)	0.0016 (8)
C10B	0.065 (2)	0.0469 (12)	0.0583 (13)	0.0125 (11)	0.0090 (12)	0.0092 (10)
O2	0.0836 (19)	0.0752 (12)	0.0755 (11)	0.0184 (10)	0.0147 (11)	0.0021 (9)

O1A—N1A	1.310 (2)	N1B—C2B	1.353 (3)
N1A—C2A	1.344 (3)	N1B—C9B	1.368 (3)
N1A—C9A	1.373 (3)	C2B—C3B	1.352 (4)
C2A—C3A	1.351 (3)	C2B—H2B	0.9300
C2A—H2A	0.9300	C3B—C4B	1.375 (4)
C3A—C4A	1.375 (4)	C3B—H3B	0.9300
C3A—H3A	0.9300	C4B—C10B	1.390 (4)
C4A—C10A	1.387 (4)	C4B—H4B	0.9300
C4A—H4A	0.9300	C5B—C10B	1.514 (4)
C5A—C6A	1.503 (4)	C5B—C6B	1.534 (5)
C5A—C10A	1.514 (3)	C5B—H51B	0.9700
C5A—H51A	0.9700	C5B—H52B	0.9700
C5A—H52A	0.9700	C6B—C7B	1.462 (5)
C6A—C7A	1.480 (4)	C6B—H61B	0.9700
C6A—H61A	0.9700	C6B—H62B	0.9700
C6A—H62A	0.9700	C7B—C8B	1.517 (4)
C7A—C8A	1.517 (3)	C7B—H71B	0.9700
C7A—H71A	0.9700	C7B—H72B	0.9700
C7A—H72A	0.9700	C8B—C9B	1.484 (3)
C8A—C9A	1.490 (3)	C8B—H81B	0.9700
C8A—H81A	0.9700	C8B—H82B	0.9700
C8A—H82A	0.9700	C9B—C10B	1.383 (4)
C9A—C10A	1.376 (3)	O2—H21	0.96 (3)
O1B—N1B	1.308 (3)	O2—H22	0.95 (4)
O1A—N1A—C2A	119.72 (18)	O1B—N1B—C9B	119.0 (2)
O1A—N1A—C9A	118.46 (17)	C2B—N1B—C9B	121.9 (2)
C2A—N1A—C9A	121.83 (19)	N1B—C2B—C3B	120.1 (2)
N1A—C2A—C3A	120.0 (2)	N1B—C2B—H2B	120.0
N1A—C2A—H2A	120.0	C3B—C2B—H2B	120.0
C3A—C2A—H2A	120.0	C2B—C3B—C4B	119.9 (3)
C2A—C3A—C4A	119.6 (2)	C2B—C3B—H3B	120.0
C2A—C3A—H3A	120.2	C4B—C3B—H3B	120.0
C4A—C3A—H3A	120.2	C3B—C4B—C10B	120.3 (3)
C3A—C4A—C10A	120.9 (2)	C3B—C4B—H4B	119.8
C3A—C4A—H4A	119.5	C10B—C4B—H4B	119.8
C10A—C4A—H4A	119.5	C10B—C5B—C6B	111.2 (3)
C6A—C5A—C10A	112.75 (19)	C10B—C5B—H51B	109.4
C6A—C5A—H51A	109.0	C6B—C5B—H51B	109.4
C10A—C5A—H51A	109.0	C10B—C5B—H52B	109.4
C6A—C5A—H52A	109.0	C6B—C5B—H52B	109.4
C10A—C5A—H52A	109.0	H51B—C5B—H52B	108.0
H51A—C5A—H52A	107.8	C7B—C6B—C5B	111.3 (3)
C7A—C6A—C5A	111.5 (2)	C7B—C6B—H61B	109.4
C7A—C6A—H61A	109.3	C5B—C6B—H61B	109.4
C5A—C6A—H61A	109.3	C7B—C6B—H62B	109.4
C7A—C6A—H62A	109.3	C5B—C6B—H62B	109.4
C5A—C6A—H62A	109.3	H61B—C6B—H62B	108.0
H61A—C6A—H62A	108.0	C6B—C7B—C8B	111.8 (2)
C6A—C7A—C8A	112.3 (2)	C6B—C7B—H71B	109.3
C6A—C7A—H71A	109.1	C8B—C7B—H71B	109.3
C8A—C7A—H71A	109.1	C6B—C7B—H72B	109.3
C6A—C7A—H72A	109.1	C8B—C7B—H72B	109.3
C8A—C7A—H72A	109.1	H71B—C7B—H72B	107.9
H71A—C7A—H72A	107.9	C9B—C8B—C7B	113.5 (3)
C9A—C8A—C7A	113.33 (19)	C9B—C8B—H81B	108.9
C9A—C8A—H81A	108.9	C7B—C8B—H81B	108.9
C7A—C8A—H81A	108.9	C9B—C8B—H82B	108.9
C9A—C8A—H82A	108.9	C7B—C8B—H82B	108.9
C7A—C8A—H82A	108.9	H81B—C8B—H82B	107.7
H81A—C8A—H82A	107.7	N1B—C9B—C10B	118.9 (2)
N1A—C9A—C10A	119.28 (19)	N1B—C9B—C8B	116.3 (2)
N1A—C9A—C8A	116.81 (18)	C10B—C9B—C8B	124.7 (2)
C10A—C9A—C8A	123.91 (19)	C9B—C10B—C4B	118.9 (2)
C9A—C10A—C4A	118.3 (2)	C9B—C10B—C5B	118.9 (3)
C9A—C10A—C5A	119.6 (2)	C4B—C10B—C5B	122.2 (3)
C4A—C10A—C5A	122.1 (2)	H21—O2—H22	102 (3)
O1B—N1B—C2B	119.10 (19)
O1A—N1A—C2A—C3A	178.4 (2)	O1B—N1B—C2B—C3B	179.9 (2)
C9A—N1A—C2A—C3A	−2.0 (4)	C9B—N1B—C2B—C3B	−0.2 (3)
N1A—C2A—C3A—C4A	0.9 (4)	N1B—C2B—C3B—C4B	0.4 (4)
C2A—C3A—C4A—C10A	0.3 (4)	C2B—C3B—C4B—C10B	−0.5 (4)
C10A—C5A—C6A—C7A	49.6 (3)	C10B—C5B—C6B—C7B	52.8 (3)
C5A—C6A—C7A—C8A	−59.9 (3)	C5B—C6B—C7B—C8B	−61.4 (3)
C6A—C7A—C8A—C9A	38.5 (3)	C6B—C7B—C8B—C9B	37.8 (3)
O1A—N1A—C9A—C10A	−178.6 (2)	O1B—N1B—C9B—C10B	−179.94 (19)
C2A—N1A—C9A—C10A	1.7 (4)	C2B—N1B—C9B—C10B	0.1 (3)
O1A—N1A—C9A—C8A	0.5 (3)	O1B—N1B—C9B—C8B	−1.3 (3)
C2A—N1A—C9A—C8A	−179.2 (2)	C2B—N1B—C9B—C8B	178.68 (18)
C7A—C8A—C9A—N1A	172.3 (2)	C7B—C8B—C9B—N1B	174.06 (19)
C7A—C8A—C9A—C10A	−8.7 (4)	C7B—C8B—C9B—C10B	−7.4 (3)
N1A—C9A—C10A—C4A	−0.5 (4)	N1B—C9B—C10B—C4B	−0.2 (3)
C8A—C9A—C10A—C4A	−179.5 (2)	C8B—C9B—C10B—C4B	−178.7 (2)
N1A—C9A—C10A—C5A	178.5 (2)	N1B—C9B—C10B—C5B	178.77 (19)
C8A—C9A—C10A—C5A	−0.6 (4)	C8B—C9B—C10B—C5B	0.3 (3)
C3A—C4A—C10A—C9A	−0.5 (4)	C3B—C4B—C10B—C9B	0.4 (3)
C3A—C4A—C10A—C5A	−179.4 (3)	C3B—C4B—C10B—C5B	−178.5 (2)
C6A—C5A—C10A—C9A	−19.7 (4)	C6B—C5B—C10B—C9B	−22.2 (3)
C6A—C5A—C10A—C4A	159.2 (3)	C6B—C5B—C10B—C4B	156.8 (3)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H21···O1A	0.96 (3)	1.87 (3)	2.825 (3)	170 (3)
O2—H22···O1B	0.95 (4)	1.86 (3)	2.799 (3)	170 (3)
C2B—H2B···O1A	0.93	2.53	3.454 (3)	171
C3A—H3A···O2i	0.93	2.50	3.392 (3)	160
C3B—H3B···O2ii	0.93	2.56	3.342 (4)	142
C5A—H52A···O1Biii	0.97	2.49	3.383 (4)	153

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H21⋯O1A	0.96 (3)	1.87 (3)	2.825 (3)	170 (3)
O2—H22⋯O1B	0.95 (4)	1.86 (3)	2.799 (3)	170 (3)
C2B—H2B⋯O1A	0.93	2.53	3.454 (3)	171
C3A—H3A⋯O2i	0.93	2.50	3.392 (3)	160
C3B—H3B⋯O2ii	0.93	2.56	3.342 (4)	142
C5A—H52A⋯O1Biii	0.97	2.49	3.383 (4)	153

Symmetry codes: (i) ; (ii) ; (iii) .