3,5-Dimethyl-2,6-diphenyl-3,4,5,6-tetra­hydro-2H-pyran-4-one

Asghar, M.N.; Arshad, M.N.; Zia-ur-Rehman, M.; Khan, I.U.; Shafiq, M.

doi:10.1107/S1600536809001792

organic compounds

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ISSN: 2056-9890

Volume 65| Part 3| March 2009| Page o463

doi:10.1107/S1600536809001792

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3,5-Dimethyl-2,6-diphenyl-3,4,5,6-tetrahydro-2H-pyran-4-one

Muhammad Nadeem Asghar,^a Muhammad Nadeem Arshad,^a Muhammad Zia-ur-Rehman,^b Islam Ullah Khan ^a ^* and Muhammad Shafiq ^a

^aDepartment of Chemistry, Government College University, Lahore 54000, Pakistan., and ^bApplied Chemistry Research Centre, PCSIR Laboratories Complex, Lahore 54600, Pakistan
^*Correspondence e-mail: iukhan.gcu@gmail.com

(Received 13 January 2009; accepted 14 January 2009; online 4 February 2009)

The molecular structure of the title compound, C₁₉H₂₀O₂, reveals a slightly distorted chair conformation for the tetrahydropyran ring with the two methyl and two phenyl substituents in equatorial positions.

Related literature

For the isolation of the title compound from its natural source and its biological activity, see: Noller (1966 ). For conformational studies, see: Belakhov et al. (2002 ); Jose Kavitha et al. (2003 ); Kumar et al. (1999 ); Ray et al. (1998 ); Usman et al. (2002 ). For the synthesis of related molecules, see: Krishnamoorthy et al. (2003 ); Parthiban et al. (2003 ).

Experimental

Crystal data

C₁₉H₂₀O₂
M_r = 280.35
Orthorhombic, P b c a
a = 14.7247 (10) Å
b = 9.2803 (7) Å
c = 23.0393 (16) Å
V = 3148.3 (4) Å³
Z = 8
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 296 (2) K
0.32 × 0.18 × 0.11 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: none
18754 measured reflections
3885 independent reflections
1969 reflections with I > 2σ(I)
R_int = 0.083

Refinement

R[F² > 2σ(F²)] = 0.050
wR(F²) = 0.163
S = 0.92
3885 reflections
190 parameters
H-atom parameters constrained
Δρ_max = 0.25 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Data collection: APEX2 (Bruker, 2006 ); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2003 ); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and local programs.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809001792/bt2850sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809001792/bt2850Isup2.hkl

checkCIF report

Comment top

Tetrahydropyran-4-one moiety has been found in various naturally occurring biologically active heterocyclic compounds (Noller, 1966). Japp and Maitland reported the synthesis of various tetrahydropyrans (Japp & Maitland, 1904) for the first time. Since then, a large number of tetrahydropyran derivatives have been reported with different conformations for the six-membered heterocyclic ring such as sofa (Ray et al., 1998), planar (Kumar et al., 1999), chair (Belakhov et al., 2002; Krishnamoorthy et al., 2003; Jose Kavitha et al., 2003) or twist boat (Usman et al., 2002). Adoption of a particular conformation mainly depends upon the number and nature of the substituents and the level of unsaturation.

In the title compound C₁₉H₂₀O₂,as shown in Fig. 1, the tetrahydropyran ring adopts a chair conformation with two methyl and two phenyl groups attached to it. All the methyl and phenyl groups occupy equatorial positions as was also reported for related molecules (Parthiban et al., 2003; Krishnamoorthy et al., 2003; Jose Kavitha et al., 2003). There are no strong intermolecular interactions between the molecules.

Related literature top

For the isolation from the natural source and biological activity, see: Noller (1966). For the synthesis of tetrahydropyrans, see: Japp & Maitland (1904). For conformational studies, see: Belakhov et al. (2002); Jose Kavitha et al. (2003); Kumar et al. (1999); Ray et al. (1998); Usman et al. (2002). For related literature, see: Krishnamoorthy et al. (2003); Parthiban et al. (2003).

Experimental top

An alcoholic solution of sodium hydroxide (8%; 10.0 ml) was added drop wise to a mixture of 3-pentanone (1.06 ml) and benzaldehyde (2.1 ml) while stirring. The contents were kept stirred for another six hours till the formation of precipitates at bottom which were washed with cold water and re-crystallized in acetone for X-Ray studies.

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and local programs.

Figures top

Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atom-numbering scheme.

3,5-Dimethyl-2,6-diphenyl-3,4,5,6-tetrahydro-2H-pyran-4-one top

Crystal data top

C₁₉H₂₀O₂	F(000) = 1200
M_r = 280.35	D_x = 1.183 Mg m⁻³
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 1807 reflections
a = 14.7247 (10) Å	θ = 2.7–21.7°
b = 9.2803 (7) Å	µ = 0.08 mm⁻¹
c = 23.0393 (16) Å	T = 296 K
V = 3148.3 (4) Å³	Needles, orange
Z = 8	0.32 × 0.18 × 0.11 mm

Data collection top

Bruker APEXII CCD area-detector diffractometer	1969 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.083
Graphite monochromator	θ_max = 28.3°, θ_min = 2.2°
Detector resolution: 7.5 pixels mm^-1	h = −12→19
ϕ and ω scans	k = −12→12
18754 measured reflections	l = −30→28
3885 independent reflections

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)] = 0.050	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.163	H-atom parameters constrained
S = 0.92	w = 1/[σ²(F_o²) + (0.0702P)²] where P = (F_o² + 2F_c²)/3
3885 reflections	(Δ/σ)_max < 0.001
190 parameters	Δρ_max = 0.25 e Å⁻³
0 restraints	Δρ_min = −0.20 e Å⁻³

Crystal data top

C₁₉H₂₀O₂	V = 3148.3 (4) Å³
M_r = 280.35	Z = 8
Orthorhombic, Pbca	Mo Kα radiation
a = 14.7247 (10) Å	µ = 0.08 mm⁻¹
b = 9.2803 (7) Å	T = 296 K
c = 23.0393 (16) Å	0.32 × 0.18 × 0.11 mm

Data collection top

Bruker APEXII CCD area-detector diffractometer	1969 reflections with I > 2σ(I)
18754 measured reflections	R_int = 0.083
3885 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.050	0 restraints
wR(F²) = 0.163	H-atom parameters constrained
S = 0.92	Δρ_max = 0.25 e Å⁻³
3885 reflections	Δρ_min = −0.20 e Å⁻³
190 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
O1	0.26436 (11)	0.0831 (2)	0.17630 (7)	0.0820 (6)
O2	0.49065 (9)	0.29668 (16)	0.21555 (6)	0.0484 (4)
C1	0.34164 (16)	0.1191 (2)	0.18707 (11)	0.0536 (6)
C2	0.37801 (14)	0.1225 (2)	0.24820 (9)	0.0509 (6)
H2	0.4268	0.0509	0.2507	0.061*
C3	0.42129 (14)	0.2730 (2)	0.25768 (9)	0.0481 (6)
H3	0.3741	0.3463	0.2524	0.058*
C4	0.40680 (15)	0.1656 (3)	0.14038 (9)	0.0524 (6)
H4	0.4528	0.0897	0.1371	0.063*
C5	0.45719 (15)	0.3048 (3)	0.15765 (9)	0.0493 (6)
H5	0.4149	0.3860	0.1549	0.059*
C6	0.46250 (14)	0.2921 (2)	0.31692 (9)	0.0466 (6)
C7	0.41229 (16)	0.3486 (2)	0.36203 (10)	0.0530 (6)
H7	0.3527	0.3773	0.3553	0.064*
C8	0.44825 (17)	0.3634 (3)	0.41681 (11)	0.0622 (7)
H8	0.4130	0.4013	0.4466	0.075*
C9	0.53592 (18)	0.3224 (3)	0.42750 (11)	0.0672 (7)
H9	0.5602	0.3317	0.4646	0.081*
C10	0.58800 (17)	0.2672 (3)	0.38303 (11)	0.0649 (7)
H10	0.6479	0.2405	0.3900	0.078*
C11	0.55156 (15)	0.2515 (3)	0.32831 (10)	0.0562 (6)
H11	0.5870	0.2133	0.2986	0.067*
C12	0.53684 (15)	0.3335 (2)	0.11866 (9)	0.0464 (6)
C13	0.61089 (15)	0.2416 (3)	0.11876 (10)	0.0581 (7)
H13	0.6120	0.1635	0.1440	0.070*
C14	0.68301 (16)	0.2649 (3)	0.08169 (13)	0.0701 (8)
H14	0.7325	0.2026	0.0823	0.084*
C15	0.68223 (19)	0.3787 (4)	0.04411 (12)	0.0749 (8)
H15	0.7307	0.3933	0.0189	0.090*
C16	0.6098 (2)	0.4710 (3)	0.04381 (11)	0.0745 (8)
H16	0.6094	0.5494	0.0187	0.089*
C17	0.53748 (17)	0.4482 (3)	0.08070 (10)	0.0607 (7)
H17	0.4884	0.5112	0.0799	0.073*
C18	0.30683 (16)	0.0820 (3)	0.29241 (11)	0.0744 (8)
H18A	0.3330	0.0846	0.3306	0.112*
H18B	0.2850	−0.0134	0.2844	0.112*
H18C	0.2573	0.1490	0.2904	0.112*
C19	0.36211 (17)	0.1792 (3)	0.08100 (11)	0.0801 (9)
H19A	0.4068	0.2073	0.0528	0.120*
H19B	0.3151	0.2507	0.0826	0.120*
H19C	0.3363	0.0881	0.0701	0.120*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0478 (10)	0.1251 (17)	0.0730 (12)	−0.0189 (11)	−0.0087 (9)	−0.0002 (11)
O2	0.0483 (9)	0.0578 (9)	0.0389 (9)	−0.0037 (7)	0.0026 (7)	0.0010 (8)
C1	0.0424 (14)	0.0601 (15)	0.0582 (16)	−0.0004 (12)	−0.0031 (12)	−0.0027 (13)
C2	0.0448 (13)	0.0581 (14)	0.0500 (15)	−0.0028 (11)	−0.0009 (12)	0.0031 (12)
C3	0.0447 (12)	0.0545 (14)	0.0450 (14)	0.0039 (11)	0.0017 (11)	0.0024 (12)
C4	0.0433 (14)	0.0677 (17)	0.0462 (14)	−0.0014 (11)	−0.0047 (12)	−0.0027 (12)
C5	0.0501 (14)	0.0552 (14)	0.0427 (14)	0.0081 (11)	−0.0033 (12)	0.0029 (11)
C6	0.0443 (13)	0.0492 (13)	0.0463 (14)	−0.0017 (11)	0.0014 (11)	0.0033 (12)
C7	0.0537 (15)	0.0565 (15)	0.0489 (15)	0.0024 (11)	0.0035 (13)	−0.0002 (12)
C8	0.0755 (18)	0.0663 (17)	0.0447 (15)	−0.0013 (14)	0.0069 (14)	−0.0003 (13)
C9	0.080 (2)	0.0714 (18)	0.0503 (16)	−0.0095 (15)	−0.0124 (16)	0.0052 (14)
C10	0.0531 (16)	0.0769 (19)	0.0646 (18)	0.0011 (13)	−0.0129 (14)	0.0070 (15)
C11	0.0509 (14)	0.0659 (16)	0.0518 (15)	0.0019 (12)	0.0004 (13)	−0.0004 (13)
C12	0.0487 (14)	0.0514 (14)	0.0391 (13)	−0.0006 (11)	−0.0002 (11)	−0.0006 (11)
C13	0.0478 (14)	0.0622 (16)	0.0644 (17)	0.0017 (12)	0.0012 (13)	0.0047 (13)
C14	0.0489 (15)	0.086 (2)	0.076 (2)	0.0030 (14)	0.0021 (15)	−0.0113 (18)
C15	0.0689 (19)	0.105 (2)	0.0512 (17)	−0.0200 (18)	0.0112 (15)	−0.0052 (17)
C16	0.089 (2)	0.083 (2)	0.0518 (17)	−0.0164 (17)	0.0014 (17)	0.0147 (15)
C17	0.0705 (17)	0.0613 (16)	0.0502 (15)	0.0059 (13)	−0.0026 (14)	0.0067 (14)
C18	0.0675 (17)	0.089 (2)	0.0669 (18)	−0.0198 (15)	0.0073 (15)	0.0073 (15)
C19	0.0700 (18)	0.120 (2)	0.0506 (17)	−0.0133 (16)	−0.0127 (14)	−0.0010 (16)

Geometric parameters (Å, º) top

O1—C1	1.212 (2)	C9—H9	0.9300
O2—C5	1.424 (2)	C10—C11	1.378 (3)
O2—C3	1.426 (2)	C10—H10	0.9300
C1—C4	1.504 (3)	C11—H11	0.9300
C1—C2	1.507 (3)	C12—C17	1.377 (3)
C2—C18	1.509 (3)	C12—C13	1.385 (3)
C2—C3	1.550 (3)	C13—C14	1.380 (3)
C2—H2	0.9800	C13—H13	0.9300
C3—C6	1.504 (3)	C14—C15	1.366 (4)
C3—H3	0.9800	C14—H14	0.9300
C4—C19	1.523 (3)	C15—C16	1.367 (4)
C4—C5	1.542 (3)	C15—H15	0.9300
C4—H4	0.9800	C16—C17	1.379 (3)
C5—C12	1.501 (3)	C16—H16	0.9300
C5—H5	0.9800	C17—H17	0.9300
C6—C7	1.379 (3)	C18—H18A	0.9600
C6—C11	1.389 (3)	C18—H18B	0.9600
C7—C8	1.376 (3)	C18—H18C	0.9600
C7—H7	0.9300	C19—H19A	0.9600
C8—C9	1.368 (3)	C19—H19B	0.9600
C8—H8	0.9300	C19—H19C	0.9600
C9—C10	1.378 (3)

C5—O2—C3	113.45 (15)	C8—C9—H9	120.2
O1—C1—C4	122.1 (2)	C10—C9—H9	120.2
O1—C1—C2	122.1 (2)	C11—C10—C9	120.2 (2)
C4—C1—C2	115.83 (18)	C11—C10—H10	119.9
C1—C2—C18	112.26 (18)	C9—C10—H10	119.9
C1—C2—C3	107.24 (17)	C10—C11—C6	120.8 (2)
C18—C2—C3	114.50 (19)	C10—C11—H11	119.6
C1—C2—H2	107.5	C6—C11—H11	119.6
C18—C2—H2	107.5	C17—C12—C13	118.1 (2)
C3—C2—H2	107.5	C17—C12—C5	121.5 (2)
O2—C3—C6	108.08 (16)	C13—C12—C5	120.3 (2)
O2—C3—C2	109.72 (17)	C14—C13—C12	120.6 (2)
C6—C3—C2	113.57 (18)	C14—C13—H13	119.7
O2—C3—H3	108.4	C12—C13—H13	119.7
C6—C3—H3	108.4	C15—C14—C13	120.5 (2)
C2—C3—H3	108.4	C15—C14—H14	119.8
C1—C4—C19	112.98 (19)	C13—C14—H14	119.8
C1—C4—C5	111.25 (18)	C14—C15—C16	119.6 (3)
C19—C4—C5	111.73 (19)	C14—C15—H15	120.2
C1—C4—H4	106.8	C16—C15—H15	120.2
C19—C4—H4	106.8	C15—C16—C17	120.2 (3)
C5—C4—H4	106.8	C15—C16—H16	119.9
O2—C5—C12	107.44 (17)	C17—C16—H16	119.9
O2—C5—C4	111.32 (18)	C12—C17—C16	121.0 (2)
C12—C5—C4	111.73 (18)	C12—C17—H17	119.5
O2—C5—H5	108.8	C16—C17—H17	119.5
C12—C5—H5	108.8	C2—C18—H18A	109.5
C4—C5—H5	108.8	C2—C18—H18B	109.5
C7—C6—C11	117.8 (2)	H18A—C18—H18B	109.5
C7—C6—C3	120.8 (2)	C2—C18—H18C	109.5
C11—C6—C3	121.3 (2)	H18A—C18—H18C	109.5
C8—C7—C6	121.5 (2)	H18B—C18—H18C	109.5
C8—C7—H7	119.2	C4—C19—H19A	109.5
C6—C7—H7	119.2	C4—C19—H19B	109.5
C9—C8—C7	120.0 (2)	H19A—C19—H19B	109.5
C9—C8—H8	120.0	C4—C19—H19C	109.5
C7—C8—H8	120.0	H19A—C19—H19C	109.5
C8—C9—C10	119.6 (2)	H19B—C19—H19C	109.5

O1—C1—C2—C18	−2.1 (3)	O2—C3—C6—C11	−34.7 (3)
C4—C1—C2—C18	177.0 (2)	C2—C3—C6—C11	87.3 (3)
O1—C1—C2—C3	−128.7 (2)	C11—C6—C7—C8	−0.6 (3)
C4—C1—C2—C3	50.3 (2)	C3—C6—C7—C8	178.4 (2)
C5—O2—C3—C6	−170.35 (17)	C6—C7—C8—C9	0.3 (4)
C5—O2—C3—C2	65.3 (2)	C7—C8—C9—C10	0.4 (4)
C1—C2—C3—O2	−57.9 (2)	C8—C9—C10—C11	−0.9 (4)
C18—C2—C3—O2	176.88 (18)	C9—C10—C11—C6	0.6 (4)
C1—C2—C3—C6	−178.93 (18)	C7—C6—C11—C10	0.1 (3)
C18—C2—C3—C6	55.8 (3)	C3—C6—C11—C10	−178.8 (2)
O1—C1—C4—C19	6.9 (3)	O2—C5—C12—C17	−125.9 (2)
C2—C1—C4—C19	−172.2 (2)	C4—C5—C12—C17	111.7 (2)
O1—C1—C4—C5	133.5 (2)	O2—C5—C12—C13	56.2 (3)
C2—C1—C4—C5	−45.6 (3)	C4—C5—C12—C13	−66.2 (3)
C3—O2—C5—C12	178.60 (17)	C17—C12—C13—C14	0.0 (3)
C3—O2—C5—C4	−58.8 (2)	C5—C12—C13—C14	177.9 (2)
C1—C4—C5—O2	46.6 (2)	C12—C13—C14—C15	−0.3 (4)
C19—C4—C5—O2	173.93 (18)	C13—C14—C15—C16	0.8 (4)
C1—C4—C5—C12	166.75 (18)	C14—C15—C16—C17	−0.9 (4)
C19—C4—C5—C12	−66.0 (2)	C13—C12—C17—C16	0.0 (3)
O2—C3—C6—C7	146.3 (2)	C5—C12—C17—C16	−178.0 (2)
C2—C3—C6—C7	−91.7 (2)	C15—C16—C17—C12	0.5 (4)

Experimental details

Crystal data
Chemical formula	C₁₉H₂₀O₂
M_r	280.35
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	296
a, b, c (Å)	14.7247 (10), 9.2803 (7), 23.0393 (16)
V (Å³)	3148.3 (4)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.32 × 0.18 × 0.11

Data collection
Diffractometer	Bruker APEXII CCD area-detector diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	18754, 3885, 1969
R_int	0.083
(sin θ/λ)_max (Å⁻¹)	0.667

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.050, 0.163, 0.92
No. of reflections	3885
No. of parameters	190
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.25, −0.20

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2003), SHELXTL (Sheldrick, 2008) and local programs.

Acknowledgements

The authors are grateful to the Higher Education Commission of Pakistan, Islamabad, for a grant for the purchase of the diffractometer.

References

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