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Acta Cryst. (2009). E65, o885    [ doi:10.1107/S1600536809010393 ]

1-Methyl-3,5-bis[(E)-(3-methyl-2-thienyl)methylene]piperidin-4-one monohydrate

K. Rajeswari, K. Pandiarajan, P. Gayathri and A. Thiruvalluvar

Abstract top

In the title molecule, C18H19NOS2·H2O, the piperidine ring adopts an envelope conformation with the methyl substituent in an equatorial position. Each of the olefinic double bonds has an E configuration. The dihedral angle between the two thiophene rings is 6.04 (14)°. The water molecule forms two donor interactions, one with the carbonyl O atom and the other to the hetero N atom. The centrosymmetric {C18H19NOS2·H2O}2 pairs thus formed are linked into a supramolecular chain via C-H...Owater contacts.

Comment top

1-N-(Arylmaleamoyl)-3,5-bis(phenylmethylene)piperidin-4-ones (Jha & Dimmock, 2006) have been proved as antimycobacterial agents. The cytotoxic properties of 3,5 bis(arylidene)piperidin-4-ones (Das et al., 2007) have also been reported. Due to the above importance, the crystal structure of the title compound (I) has been determined by X-ray diffraction.

The piperidine ring in (I), Fig. 1, adopts an envelope conformation with the methyl substituent in an equatorial position. The sum of the bond angles around N1 [330.9 (2)°] indicates a pyramidal geometry. The N1 atom deviates by -0.645 (3) Å from the least-squares plane passing through atoms C2—C6 . Both olefinic double bonds have an E-configuration. The thiophene rings are co-planar with the adjacent olefinic double bonds and the planar portion of piperidone ring. The dihedral angle between the two thiophene rings is 6.04 (14)°. The molecular conformation is stabilized by weak C—H···O and C—H···S contacts, Table 1. The water molecules forms two O—H donor interactions, one with the carbonyl-O atom and other to the amine-N atom, Table 1. These hydrogen bonds result in the formation of a centrosymmetric {C18H19NOS2.H2O}2 pair, and these are linked into supramolecular chains via C35-H···O contacts, Table 1. Additional stabilisation to the crystal strucutre is afforded by C-H···O and C-H···π contacts, as detailed in Table 1 and illustrated in Fig. 2.

Related literature top

For piperidine-4-ones as antimycobacterial agents, see: Jha & Dimmock (2006). For their cytotoxic properties, see: Das et al. (2007).

Experimental top

To a mixture of N-methylpiperidin-4-one (1.5 ml, 0.01 mol) and 3-methylthiophene-2-aldehyde (2.7 ml, 0.02 mol) in ethanol (95%, 10 ml), sodium hydroxide (20%, 5 ml) was added. The solution was heated on a waterbath for 30 mins. The solid that separated on cooling was filtered and was recrystallized from 95% ethanol in a yield of 2.5 g (80%).

Refinement top

The water-H atoms, H1A and H1B, were located in a difference density Fourier map and included in the refinement with the O—H distances restrained to be 0.86±0.01 Å, with the H···H distance restrained to 1.373 Å, and with Uiso(H) = 1.5 times Ueq(O). The remaining H atoms were positioned geometrically and allowed to ride on their parent atoms with C—H = 0.93 - 0.97 Å, and with Uiso(H) = 1.2 - 1.5 times Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT-NT (Bruker, 2004); data reduction: SAINT-NT (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: PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), showing the atom-numbering scheme and displacement ellipsoids drawn at the 30% probability level. H atoms are shown as small spheres of arbitrary radius.
[Figure 2] Fig. 2. A view down the b axis of the packing in (I). Dashed lines indicate hydrogen bonds. The H atoms not involved in hydrogen bonding have been omitted for reasons of clarity.
1-Methyl-3,5-bis[(E)-(3-methyl-2-thienyl)methylene]piperidin-4-one monohydrate top
Crystal data top
C18H19NOS2·H2OZ = 2
Mr = 347.50F(000) = 368
Triclinic, P1Dx = 1.290 Mg m−3
Hall symbol: -P 1Melting point: 423 K
a = 7.5781 (7) ÅMo Kα radiation, λ = 0.71073 Å
b = 10.9926 (9) ÅCell parameters from 9874 reflections
c = 11.5304 (10) Åθ = 2.0–25.0°
α = 79.531 (2)°µ = 0.31 mm−1
β = 83.404 (2)°T = 293 K
γ = 71.673 (2)°Prism, colourless
V = 894.90 (14) Å30.36 × 0.22 × 0.22 mm
Data collection top
Bruker Kappa APEXII CCD
diffractometer		3127 independent reflections
Radiation source: fine-focus sealed tube2686 reflections with I > 2σ(I)
graphiteRint = 0.021
Detector resolution: 0 pixels mm-1θmax = 25.0°, θmin = 2.0°
ω and φ scansh = −9→9
Absorption correction: multi-scan
(SADABS; Bruker, 2004)		k = −13→13
Tmin = 0.901, Tmax = 0.938l = −13→13
15827 measured reflections
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)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.130H atoms treated by a mixture of independent and constrained refinement
S = 1.11 w = 1/[σ2(Fo2) + (0.0602P)2 + 0.4317P]
where P = (Fo2 + 2Fc2)/3
3127 reflections(Δ/σ)max = 0.001
217 parametersΔρmax = 0.44 e Å−3
3 restraintsΔρmin = −0.31 e Å−3
Crystal data top
C18H19NOS2·H2Oγ = 71.673 (2)°
Mr = 347.50V = 894.90 (14) Å3
Triclinic, P1Z = 2
a = 7.5781 (7) ÅMo Kα radiation
b = 10.9926 (9) ŵ = 0.31 mm−1
c = 11.5304 (10) ÅT = 293 K
α = 79.531 (2)°0.36 × 0.22 × 0.22 mm
β = 83.404 (2)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer		3127 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2004)		2686 reflections with I > 2σ(I)
Tmin = 0.901, Tmax = 0.938Rint = 0.021
15827 measured reflectionsθmax = 25.0°
Refinement top
R[F2 > 2σ(F2)] = 0.043H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.130Δρmax = 0.44 e Å−3
S = 1.11Δρmin = −0.31 e Å−3
3127 reflectionsAbsolute structure: ?
217 parametersFlack parameter: ?
3 restraintsRogers parameter: ?
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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 > 2σ(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
S310.12090 (9)0.66376 (7)0.92973 (5)0.0616 (2)
S510.60928 (9)0.12751 (6)0.41757 (6)0.0613 (2)
O40.1381 (3)0.60702 (18)0.46923 (16)0.0789 (7)
N10.3386 (3)0.31766 (17)0.73473 (15)0.0491 (6)
C20.3009 (4)0.4473 (2)0.7629 (2)0.0561 (8)
C30.1977 (3)0.5506 (2)0.67020 (19)0.0481 (7)
C40.2189 (3)0.5242 (2)0.54771 (19)0.0517 (7)
C50.3416 (3)0.3973 (2)0.52192 (19)0.0491 (7)
C60.4442 (3)0.3036 (2)0.6214 (2)0.0562 (8)
C110.4415 (4)0.2222 (3)0.8279 (2)0.0644 (9)
C130.0932 (3)0.6700 (2)0.6881 (2)0.0496 (7)
C150.3552 (3)0.3766 (2)0.40958 (19)0.0503 (7)
C320.0478 (3)0.7334 (2)0.7898 (2)0.0508 (7)
C33−0.0590 (3)0.8610 (2)0.7893 (2)0.0580 (8)
C34−0.0799 (4)0.8984 (3)0.9011 (3)0.0717 (10)
C350.0091 (4)0.8029 (3)0.9852 (3)0.0747 (11)
C36−0.1438 (4)0.9519 (3)0.6826 (3)0.0700 (9)
C520.4595 (3)0.2700 (2)0.3507 (2)0.0520 (8)
C530.4559 (3)0.2664 (3)0.2315 (2)0.0564 (8)
C540.5707 (4)0.1487 (3)0.1991 (2)0.0660 (9)
C550.6615 (4)0.0657 (3)0.2886 (3)0.0688 (10)
C560.3477 (4)0.3754 (3)0.1436 (2)0.0733 (10)
O1W0.0177 (4)0.2338 (3)0.7303 (2)0.1048 (11)
H2A0.417930.461990.772000.0673*
H2B0.228270.453490.837750.0673*
H6A0.468570.215720.606100.0675*
H6B0.563080.318110.625160.0675*
H11A0.556530.238810.834940.0966*
H11B0.467320.136700.808580.0966*
H11C0.368290.228280.901530.0966*
H130.039310.721880.620500.0595*
H150.281750.445740.359910.0604*
H34−0.148370.981020.916130.0860*
H350.008910.812271.063750.0897*
H36A−0.059850.935300.614290.1049*
H36B−0.166381.039850.694440.1049*
H36C−0.259320.938600.670700.1049*
H540.582820.129870.122610.0792*
H550.74340−0.016050.281080.0825*
H56A0.260730.440020.184850.1096*
H56B0.281370.342200.097100.1096*
H56C0.432050.413570.092670.1096*
H1A0.099 (5)0.273 (4)0.734 (4)0.1573*
H1B−0.046 (5)0.280 (4)0.672 (3)0.1573*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S310.0677 (4)0.0680 (4)0.0491 (4)−0.0236 (3)−0.0051 (3)−0.0026 (3)
S510.0647 (4)0.0559 (4)0.0604 (4)−0.0181 (3)−0.0016 (3)−0.0035 (3)
O40.0979 (14)0.0685 (12)0.0485 (10)0.0049 (10)−0.0227 (10)0.0036 (9)
N10.0583 (11)0.0452 (10)0.0402 (9)−0.0132 (8)−0.0086 (8)0.0021 (8)
C20.0684 (15)0.0514 (13)0.0466 (12)−0.0150 (11)−0.0143 (11)−0.0016 (10)
C30.0477 (12)0.0487 (12)0.0466 (12)−0.0157 (10)−0.0068 (9)0.0008 (9)
C40.0536 (13)0.0521 (13)0.0446 (12)−0.0123 (10)−0.0099 (10)0.0025 (10)
C50.0491 (12)0.0531 (12)0.0436 (11)−0.0169 (10)−0.0050 (9)0.0003 (9)
C60.0559 (14)0.0571 (14)0.0469 (12)−0.0084 (11)−0.0046 (10)−0.0002 (10)
C110.0805 (18)0.0536 (14)0.0501 (13)−0.0102 (12)−0.0153 (12)0.0041 (11)
C130.0463 (12)0.0500 (12)0.0493 (12)−0.0143 (10)−0.0070 (9)0.0025 (10)
C150.0509 (12)0.0545 (13)0.0444 (12)−0.0182 (10)−0.0071 (9)0.0021 (10)
C320.0451 (12)0.0544 (13)0.0522 (13)−0.0176 (10)−0.0021 (10)−0.0021 (10)
C330.0458 (12)0.0588 (14)0.0672 (15)−0.0147 (10)0.0035 (11)−0.0106 (12)
C340.0656 (16)0.0710 (17)0.0754 (18)−0.0145 (14)0.0074 (14)−0.0215 (14)
C350.0772 (19)0.093 (2)0.0607 (16)−0.0330 (16)0.0111 (14)−0.0255 (15)
C360.0591 (15)0.0571 (15)0.0807 (18)−0.0026 (12)−0.0072 (13)−0.0027 (13)
C520.0513 (13)0.0602 (14)0.0497 (12)−0.0272 (11)−0.0026 (10)−0.0036 (10)
C530.0563 (14)0.0712 (15)0.0519 (13)−0.0328 (12)−0.0003 (10)−0.0129 (11)
C540.0687 (16)0.0806 (18)0.0608 (15)−0.0361 (14)0.0044 (13)−0.0224 (14)
C550.0650 (16)0.0635 (16)0.0848 (19)−0.0271 (13)0.0106 (14)−0.0246 (14)
C560.0785 (18)0.099 (2)0.0501 (14)−0.0375 (16)−0.0123 (13)−0.0066 (14)
O1W0.114 (2)0.126 (2)0.0823 (15)−0.0674 (16)−0.0458 (14)0.0452 (14)
Geometric parameters (Å, °) top
S31—C321.728 (2)C53—C561.506 (4)
S31—C351.698 (3)C53—C541.401 (4)
S51—C521.726 (2)C54—C551.341 (4)
S51—C551.701 (3)C2—H2A0.9700
O4—C41.225 (3)C2—H2B0.9700
O1W—H1A0.86 (4)C6—H6B0.9700
O1W—H1B0.86 (4)C6—H6A0.9700
N1—C111.460 (3)C11—H11C0.9600
N1—C21.452 (3)C11—H11B0.9600
N1—C61.459 (3)C11—H11A0.9600
C2—C31.495 (3)C13—H130.9300
C3—C41.474 (3)C15—H150.9300
C3—C131.342 (3)C34—H340.9300
C4—C51.473 (3)C35—H350.9300
C5—C151.342 (3)C36—H36A0.9600
C5—C61.501 (3)C36—H36C0.9600
C13—C321.426 (3)C36—H36B0.9600
C15—C521.429 (3)C54—H540.9300
C32—C331.381 (3)C55—H550.9300
C33—C341.400 (4)C56—H56C0.9600
C33—C361.502 (4)C56—H56A0.9600
C34—C351.354 (5)C56—H56B0.9600
C52—C531.386 (3)
S31···C23.200 (2)C54···H36Ciii2.9700
S31···C54i3.611 (3)C55···H36Ciii3.0400
S51···C63.208 (2)C56···H152.6900
S51···C13i3.614 (2)H1A···N12.03 (4)
S51···C36ii3.669 (3)H1A···C22.88 (4)
S31···H56Biii3.1200H1A···H35iv2.5000
S31···H2B2.5800H1A···C112.78 (4)
S51···H6A2.5300H1A···C62.87 (4)
O1W···N12.867 (4)H1B···O4iii1.91 (4)
O1W···O4iii2.759 (3)H2A···H11A2.3600
O1W···C35iv3.222 (4)H2A···H6B2.4600
O4···O1Wiii2.759 (3)H2B···C322.9200
O1W···H55v2.5200H2B···H11C2.3800
O1W···H35iv2.3400H2B···S312.5800
O4···H152.2800H6A···S512.5300
O4···H132.2600H6A···H11B2.3400
O4···H6Bi2.7000H6A···C522.9000
O4···H1Biii1.91 (4)H6B···H11A2.4200
N1···O1W2.867 (4)H6B···H2A2.4600
N1···H1A2.03 (4)H6B···O4i2.7000
C2···S313.200 (2)H6B···C4i3.0800
C6···S513.208 (2)H11A···H2A2.3600
C13···S51i3.614 (2)H11A···H6B2.4200
C32···C55i3.525 (4)H11B···H6A2.3400
C32···C56iii3.521 (4)H11C···H2B2.3800
C32···C54i3.543 (4)H11C···C35iv3.1000
C33···C55i3.342 (4)H13···C362.6600
C35···O1Wiv3.222 (4)H13···H36A2.2200
C36···S51vi3.669 (3)H13···O42.2600
C54···C32i3.543 (4)H15···O42.2800
C54···S31i3.611 (3)H15···C562.6900
C55···C32i3.525 (4)H15···H56A2.0600
C55···C33i3.342 (4)H34···H36B2.5300
C56···C32iii3.521 (4)H35···H1Aiv2.5000
C2···H1A2.88 (4)H35···O1Wiv2.3400
C4···H6Bi3.0800H36A···C132.7900
C6···H1A2.87 (4)H36A···H132.2200
C11···H1A2.78 (4)H36B···H342.5300
C13···H36A2.7900H36C···C55iii3.0400
C15···H56A2.6800H36C···C53iii3.0600
C32···H2B2.9200H36C···C54iii2.9700
C32···H56Biii2.9600H55···O1Wv2.5200
C35···H11Civ3.1000H56A···H152.0600
C36···H132.6600H56A···C152.6800
C52···H6A2.9000H56B···S31iii3.1200
C53···H36Ciii3.0600H56B···C32iii2.9600
C32—S31—C3592.06 (14)H2A—C2—H2B108.00
C52—S51—C5591.93 (14)C3—C2—H2A109.00
H1A—O1W—H1B104 (4)N1—C6—H6A109.00
C2—N1—C6111.48 (18)C5—C6—H6A109.00
C2—N1—C11109.72 (19)C5—C6—H6B109.00
C6—N1—C11109.73 (19)N1—C6—H6B109.00
N1—C2—C3112.71 (19)H6A—C6—H6B108.00
C2—C3—C4118.61 (19)N1—C11—H11B109.00
C2—C3—C13125.0 (2)N1—C11—H11C109.00
C4—C3—C13116.3 (2)H11A—C11—H11B109.00
O4—C4—C3120.4 (2)H11A—C11—H11C109.00
O4—C4—C5121.1 (2)H11B—C11—H11C109.00
C3—C4—C5118.50 (19)N1—C11—H11A109.00
C4—C5—C15116.6 (2)C3—C13—H13113.00
C6—C5—C15125.4 (2)C32—C13—H13114.00
C4—C5—C6117.98 (18)C52—C15—H15113.00
N1—C6—C5111.81 (19)C5—C15—H15113.00
C3—C13—C32133.0 (2)C33—C34—H34123.00
C5—C15—C52133.1 (2)C35—C34—H34123.00
S31—C32—C33110.37 (17)C34—C35—H35124.00
C13—C32—C33124.3 (2)S31—C35—H35124.00
S31—C32—C13125.32 (17)C33—C36—H36A109.00
C32—C33—C36125.1 (2)C33—C36—H36C109.00
C34—C33—C36122.7 (2)H36A—C36—H36B109.00
C32—C33—C34112.2 (2)H36A—C36—H36C109.00
C33—C34—C35113.6 (3)H36B—C36—H36C109.00
S31—C35—C34111.7 (3)C33—C36—H36B110.00
S51—C52—C15124.92 (17)C55—C54—H54123.00
S51—C52—C53110.18 (18)C53—C54—H54123.00
C15—C52—C53124.9 (2)S51—C55—H55124.00
C52—C53—C56125.4 (3)C54—C55—H55124.00
C54—C53—C56122.5 (2)C53—C56—H56B109.00
C52—C53—C54112.1 (2)C53—C56—H56C109.00
C53—C54—C55113.8 (2)C53—C56—H56A110.00
S51—C55—C54112.0 (2)H56A—C56—H56C109.00
N1—C2—H2A109.00H56B—C56—H56C109.00
N1—C2—H2B109.00H56A—C56—H56B109.00
C3—C2—H2B109.00
C35—S31—C32—C13179.2 (2)C4—C5—C6—N131.7 (3)
C35—S31—C32—C330.3 (2)C15—C5—C6—N1−150.0 (2)
C32—S31—C35—C34−0.1 (3)C4—C5—C15—C52178.7 (2)
C55—S51—C52—C15179.7 (2)C6—C5—C15—C520.3 (4)
C55—S51—C52—C53−0.7 (2)C3—C13—C32—S31−1.2 (4)
C52—S51—C55—C540.2 (3)C3—C13—C32—C33177.5 (3)
C6—N1—C2—C357.5 (3)C5—C15—C52—S51−0.2 (4)
C11—N1—C2—C3179.2 (2)C5—C15—C52—C53−179.8 (3)
C2—N1—C6—C5−59.9 (3)S31—C32—C33—C34−0.5 (3)
C11—N1—C6—C5178.4 (2)S31—C32—C33—C36179.2 (2)
N1—C2—C3—C4−26.9 (3)C13—C32—C33—C34−179.4 (2)
N1—C2—C3—C13156.9 (2)C13—C32—C33—C360.2 (4)
C2—C3—C4—O4−179.2 (2)C32—C33—C34—C350.4 (4)
C2—C3—C4—C5−0.3 (3)C36—C33—C34—C35−179.2 (3)
C13—C3—C4—O4−2.7 (4)C33—C34—C35—S31−0.2 (4)
C13—C3—C4—C5176.3 (2)S51—C52—C53—C541.1 (3)
C2—C3—C13—C32−0.3 (4)S51—C52—C53—C56−177.2 (2)
C4—C3—C13—C32−176.6 (2)C15—C52—C53—C54−179.3 (2)
O4—C4—C5—C6176.6 (2)C15—C52—C53—C562.4 (4)
O4—C4—C5—C15−1.9 (4)C52—C53—C54—C55−1.0 (4)
C3—C4—C5—C6−2.3 (3)C56—C53—C54—C55177.4 (3)
C3—C4—C5—C15179.2 (2)C53—C54—C55—S510.4 (4)
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x+1, y−1, z; (iii) −x, −y+1, −z+1; (iv) −x, −y+1, −z+2; (v) −x+1, −y, −z+1; (vi) x−1, y+1, z.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1W—H1A···N10.86 (4)2.03 (4)2.867 (4)164 (4)
O1W—H1B···O4iii0.86 (4)1.91 (4)2.759 (3)167 (4)
C2—H2B···S310.972.583.200 (2)122
C6—H6A···S510.972.533.208 (2)127
C13—H13···O40.932.262.693 (3)108
C15—H15···O40.932.282.711 (3)108
C35—H35···O1Wiv0.932.343.222 (4)159
C55—H55···O1Wv0.932.523.450 (4)176
C56—H56B···Cg(1)iii0.962.973.763 (3)141
C36—H36C···Cg(2)iii0.962.833.742 (3)159
Symmetry codes: (iii) −x, −y+1, −z+1; (iv) −x, −y+1, −z+2; (v) −x+1, −y, −z+1.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1W—H1A···N10.86 (4)2.03 (4)2.867 (4)164 (4)
O1W—H1B···O4i0.86 (4)1.91 (4)2.759 (3)167 (4)
C2—H2B···S310.972.583.200 (2)122
C6—H6A···S510.972.533.208 (2)127
C13—H13···O40.932.262.693 (3)108
C15—H15···O40.932.282.711 (3)108
C35—H35···O1Wii0.932.343.222 (4)159
C55—H55···O1Wiii0.932.523.450 (4)176
C56—H56B···Cg(1)i0.962.973.763 (3)141
C36—H36C···Cg(2)i0.962.833.742 (3)159
Symmetry codes: (i) −x, −y+1, −z+1; (ii) −x, −y+1, −z+2; (iii) −x+1, −y, −z+1.
Acknowledgements top

The authors are grateful to Dr A. Babu Vargheese, Sophisticated Analytical Instrument Facility (SAIF), IIT-Madras, Chennai, for the X-ray data collection.

references
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