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Acta Cryst. (2009). E65, o2429    [ doi:10.1107/S1600536809035697 ]

Dimethyl 2-butyl-2-(3,5-di-tert-butyl-4-hydroxybenzyl)malonate

T. Zeng and W.-Z. Ren

Abstract top

The title compound, C25H38O5, was formed by the reaction of dimethyl 2-butylmalonate and 2,6-di-tert-butyl-4-[(dimethylamino)methyl]phenol. In the crystal structure, molecules are linked by intermolecular O-H...O hydrogen bonds into chains along [010].

Comment top

Hindered phenols are widely used as antioxidants while hindered amines are used as light stabilizers in polymers and lubricants because of their special structures (Denisov, 1991; Klemchuk & Gande, 1998; Yamazaki & Seguchi, 1997). In a former paper (Zeng & Chen, 2006), we reported the crystal structure of bis(1,2,2,6,6-pentamethylpiperidin-4-yl)butylmalonate, a key intermediate in the peparation of 'Tinuvin 144' which is a light stabilizer of the hindered amine class that also contains an oxidant unit of the sterically hindered phenol type (Rasberger, 1980; Eggensperger et al., 1974;1976). The title compound was prepared as an intermediate when we attempted to synthesize 'Tinuvin 144' by a different route.

The molecular structure of the title compound (I) is shown in Fig. 1. The phenolic hydroxyl group is sterically hindered by the adjacent bulky tert-butyl groups as is indicated by a shorter than normal H···H contact [H1···H9B = 1.87Å]. In the crystal structure, molecules are linked by intermolecular O-H···O hydrogen bonds into one-dimensional chains along [010] (see Fig. 2).

Related literature top

For background tohindered phenols and hindered amines, see: Rasberger (1980); Yamazaki & Seguchi (1997); Eggensperger et al. (1974, 1976); Denisov (1991); Klemchuk & Gande (1998). For a related structure, see: Zeng & Chen (2006).

Experimental top

A mixture of bis(1,2,2,6,6-pentamethylpiperidin-4-yl) 2-butylmalonate (11.67 g,0.025 mol) and 2,6-di-tert-butyl-4-((dimethylamino)methyl)phenol (6.59 g, 0.025 mol)was dissloved in toluene (100 ml), stirred and heated to reflux. Then 0.2 g lithium amide was added and stirred for a further 4 h, followed by extraction with ether (30 ml) and drying with anhydrous magnesium sulfate. The solvent was removed by vacuum evaporation at 318 K, and the product was filtered and washed with methanol (10 ml). The title compound (I) (15.05 g) was obtained in 87.9% yield. Suitable crystals (m.p. 420–422 K) were obtained by slow evaporation of a solution of (I) in a mixture of THF and methanol.

Refinement top

The H atom of the O—H group was initially located in a difference Fourier map but subsequently included in a calculated position O—H = 0.82 Å and Uiso(H) = 1.5Ueq(O). All other H atoms were positioned geometrically with C-H distances in the range 0.93–0.97 Å, and they were refined using a riding-model approximation with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(C) for methyl H atoms.

Computing details top

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

Figures top
[Figure 1] Fig. 1. The molecular structure of (I). Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii.
[Figure 2] Fig. 2. Part of the crystal structure of (I) with dashed lines indicating O—H···O hydrogen bonds. Only H atoms involved in hydrogen bonds are shown.
Dimethyl 2-butyl-2-(3,5-di-tert-butyl-4-hydroxybenzyl)malonate top
Crystal data top
C24H38O5F(000) = 888
Mr = 406.54Dx = 1.063 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 2194 reflections
a = 10.854 (2) Åθ = 2.2–21.1°
b = 10.341 (2) ŵ = 0.07 mm−1
c = 22.899 (5) ÅT = 294 K
β = 98.838 (4)°Block, colourless
V = 2539.7 (9) Å30.24 × 0.20 × 0.16 mm
Z = 4
Data collection top
Bruker SMART CCD
diffractometer		4475 independent reflections
Radiation source: fine-focus sealed tube2448 reflections with I > 2σ(I)
graphiteRint = 0.048
φ and ω scansθmax = 25.0°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −11→12
Tmin = 0.983, Tmax = 0.988k = −12→11
12778 measured reflectionsl = −27→21
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)] = 0.048Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.142H-atom parameters constrained
S = 1.01 w = 1/[σ2(Fo2) + (0.0654P)2 + 0.1568P]
where P = (Fo2 + 2Fc2)/3
4475 reflections(Δ/σ)max < 0.001
272 parametersΔρmax = 0.16 e Å−3
12 restraintsΔρmin = −0.18 e Å−3
Crystal data top
C24H38O5V = 2539.7 (9) Å3
Mr = 406.54Z = 4
Monoclinic, P21/nMo Kα radiation
a = 10.854 (2) ŵ = 0.07 mm−1
b = 10.341 (2) ÅT = 294 K
c = 22.899 (5) Å0.24 × 0.20 × 0.16 mm
β = 98.838 (4)°
Data collection top
Bruker SMART CCD
diffractometer		4475 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		2448 reflections with I > 2σ(I)
Tmin = 0.983, Tmax = 0.988Rint = 0.048
12778 measured reflectionsθmax = 25.0°
Refinement top
R[F2 > 2σ(F2)] = 0.048H-atom parameters constrained
wR(F2) = 0.142Δρmax = 0.16 e Å−3
S = 1.01Δρmin = −0.18 e Å−3
4475 reflectionsAbsolute structure: ?
272 parametersFlack parameter: ?
12 restraintsRogers parameter: ?
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
xyzUiso*/Ueq
O10.41570 (13)1.09610 (18)0.27640 (6)0.0596 (5)
H10.36221.11190.29710.089*
O20.11836 (16)0.68114 (18)0.10961 (7)0.0672 (5)
O3−0.01613 (15)0.81627 (17)0.05786 (7)0.0607 (5)
O40.11420 (16)0.87050 (17)−0.07043 (7)0.0645 (5)
O50.07880 (19)0.67112 (18)−0.04056 (7)0.0780 (6)
C10.35939 (19)1.0593 (2)0.22102 (8)0.0374 (5)
C20.44117 (18)1.0357 (2)0.18030 (9)0.0364 (5)
C30.3872 (2)1.0021 (2)0.12350 (9)0.0400 (5)
H30.43930.98630.09560.048*
C40.25997 (19)0.9908 (2)0.10623 (8)0.0366 (5)
C50.18367 (19)1.01343 (19)0.14827 (8)0.0362 (5)
H50.09781.00680.13710.043*
C60.22977 (18)1.04564 (19)0.20643 (9)0.0344 (5)
C70.14008 (18)1.0678 (2)0.25207 (9)0.0397 (5)
C80.1437 (2)1.2092 (2)0.27215 (10)0.0550 (7)
H8A0.11701.26390.23880.082*
H8B0.22731.23170.28930.082*
H8C0.08921.22050.30100.082*
C90.1722 (2)0.9759 (2)0.30526 (10)0.0564 (7)
H9A0.11360.98820.33220.085*
H9B0.25480.99410.32510.085*
H9C0.16810.88800.29160.085*
C100.0049 (2)1.0388 (3)0.22531 (10)0.0609 (7)
H10A−0.04811.05140.25480.091*
H10B−0.00160.95090.21180.091*
H10C−0.02051.09590.19260.091*
C110.58343 (19)1.0484 (2)0.19695 (10)0.0456 (6)
C120.6333 (2)0.9627 (3)0.24987 (11)0.0730 (8)
H12A0.72170.97460.25990.109*
H12B0.61580.87370.23990.109*
H12C0.59360.98610.28300.109*
C130.6192 (2)1.1891 (3)0.21131 (13)0.0798 (9)
H13A0.58851.24270.17800.120*
H13B0.70831.19640.21990.120*
H13C0.58311.21660.24500.120*
C140.6513 (2)1.0060 (3)0.14653 (11)0.0823 (10)
H14A0.62551.05940.11260.123*
H14B0.63140.91740.13680.123*
H14C0.73961.01450.15860.123*
C150.2057 (2)0.9562 (2)0.04293 (8)0.0418 (6)
H15A0.26160.98780.01690.050*
H15B0.12681.00080.03260.050*
C160.1842 (2)0.8100 (2)0.03162 (8)0.0404 (6)
C170.0948 (2)0.7595 (2)0.07120 (10)0.0454 (6)
C18−0.1102 (3)0.7799 (3)0.09247 (13)0.0861 (10)
H18A−0.14290.69650.08000.129*
H18B−0.17620.84260.08710.129*
H18C−0.07430.77650.13350.129*
C190.1224 (2)0.7911 (2)−0.03234 (10)0.0485 (6)
C200.0126 (4)0.6420 (3)−0.09909 (12)0.1183 (14)
H20A−0.05920.6970−0.10750.177*
H20B−0.01360.5532−0.10060.177*
H20C0.06670.6565−0.12790.177*
C210.3054 (2)0.7306 (2)0.04303 (10)0.0499 (6)
H21A0.34740.75030.08250.060*
H21B0.28350.63960.04230.060*
C220.3966 (2)0.7522 (3)0.00000 (11)0.0655 (7)
H22A0.35940.7213−0.03870.079*
H22B0.41090.8444−0.00320.079*
C230.5202 (3)0.6857 (3)0.01765 (13)0.0813 (9)
H23A0.50480.59610.02690.098*
H23B0.56260.72590.05340.098*
C240.6056 (3)0.6890 (3)−0.02852 (16)0.1106 (12)
H24A0.56470.6494−0.06420.166*
H24B0.68080.6425−0.01430.166*
H24C0.62570.7771−0.03640.166*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0364 (9)0.1016 (14)0.0393 (9)−0.0034 (9)0.0012 (7)−0.0246 (9)
O20.0723 (13)0.0773 (13)0.0512 (11)−0.0060 (10)0.0072 (9)0.0247 (10)
O30.0506 (11)0.0706 (12)0.0615 (11)0.0020 (9)0.0102 (9)0.0068 (9)
O40.0879 (14)0.0687 (13)0.0331 (9)−0.0081 (10)−0.0027 (9)0.0055 (9)
O50.1241 (17)0.0569 (13)0.0447 (10)−0.0224 (11)−0.0135 (10)−0.0085 (8)
C10.0365 (13)0.0437 (14)0.0309 (12)−0.0030 (10)0.0018 (10)−0.0057 (10)
C20.0344 (12)0.0369 (13)0.0373 (13)−0.0036 (10)0.0040 (10)−0.0016 (10)
C30.0431 (14)0.0418 (14)0.0366 (13)−0.0012 (10)0.0107 (11)−0.0020 (10)
C40.0412 (13)0.0359 (13)0.0326 (12)0.0011 (10)0.0050 (10)0.0016 (10)
C50.0345 (12)0.0369 (13)0.0357 (12)−0.0021 (10)0.0011 (10)−0.0015 (10)
C60.0342 (13)0.0347 (13)0.0346 (12)−0.0002 (9)0.0057 (10)−0.0029 (9)
C70.0329 (12)0.0488 (15)0.0377 (12)−0.0001 (10)0.0065 (10)−0.0055 (11)
C80.0520 (16)0.0604 (18)0.0524 (15)0.0115 (12)0.0077 (12)−0.0132 (12)
C90.0606 (16)0.0639 (18)0.0474 (14)−0.0046 (13)0.0171 (12)−0.0003 (12)
C100.0394 (14)0.089 (2)0.0565 (16)−0.0098 (13)0.0135 (12)−0.0126 (14)
C110.0326 (13)0.0545 (16)0.0501 (14)−0.0056 (11)0.0082 (11)−0.0040 (11)
C120.0417 (16)0.089 (2)0.0850 (19)0.0067 (14)0.0009 (14)0.0169 (16)
C130.0532 (18)0.070 (2)0.115 (2)−0.0186 (14)0.0079 (17)−0.0108 (17)
C140.0392 (16)0.136 (3)0.0758 (19)−0.0085 (16)0.0207 (14)−0.0216 (19)
C150.0512 (14)0.0433 (14)0.0294 (12)−0.0009 (11)0.0022 (10)0.0007 (10)
C160.0520 (15)0.0435 (14)0.0245 (11)−0.0007 (11)0.0024 (10)0.0021 (10)
C170.0540 (16)0.0446 (15)0.0348 (13)−0.0055 (12)−0.0015 (12)−0.0046 (11)
C180.0618 (19)0.108 (3)0.095 (2)−0.0141 (17)0.0302 (17)−0.0006 (19)
C190.0607 (17)0.0496 (17)0.0345 (14)−0.0012 (13)0.0048 (12)−0.0024 (12)
C200.180 (4)0.099 (3)0.0592 (19)−0.035 (2)−0.034 (2)−0.0227 (18)
C210.0611 (16)0.0472 (15)0.0400 (13)0.0031 (12)0.0034 (12)−0.0008 (11)
C220.0691 (19)0.0700 (19)0.0591 (17)0.0084 (15)0.0154 (15)−0.0021 (14)
C230.075 (2)0.074 (2)0.099 (2)0.0108 (16)0.0258 (18)−0.0095 (17)
C240.093 (3)0.108 (3)0.142 (3)0.013 (2)0.052 (2)0.002 (2)
Geometric parameters (Å, °) top
O1—C11.374 (2)C12—H12A0.9600
O1—H10.8200C12—H12B0.9600
O2—C171.195 (3)C12—H12C0.9600
O3—C171.332 (3)C13—H13A0.9600
O3—C181.435 (3)C13—H13B0.9600
O4—C191.191 (3)C13—H13C0.9600
O5—C191.331 (3)C14—H14A0.9600
O5—C201.452 (3)C14—H14B0.9600
C1—C61.402 (3)C14—H14C0.9600
C1—C21.404 (3)C15—C161.546 (3)
C2—C31.386 (3)C15—H15A0.9700
C2—C111.538 (3)C15—H15B0.9700
C3—C41.382 (3)C16—C171.518 (3)
C3—H30.9300C16—C191.527 (3)
C4—C51.383 (3)C16—C211.539 (3)
C4—C151.521 (3)C18—H18A0.9600
C5—C61.389 (3)C18—H18B0.9600
C5—H50.9300C18—H18C0.9600
C6—C71.551 (3)C20—H20A0.9600
C7—C81.531 (3)C20—H20B0.9600
C7—C101.531 (3)C20—H20C0.9600
C7—C91.543 (3)C21—C221.517 (3)
C8—H8A0.9600C21—H21A0.9700
C8—H8B0.9600C21—H21B0.9700
C8—H8C0.9600C22—C231.507 (3)
C9—H9A0.9600C22—H22A0.9700
C9—H9B0.9600C22—H22B0.9700
C9—H9C0.9600C23—C241.510 (3)
C10—H10A0.9600C23—H23A0.9700
C10—H10B0.9600C23—H23B0.9700
C10—H10C0.9600C24—H24A0.9600
C11—C141.526 (3)C24—H24B0.9600
C11—C131.528 (3)C24—H24C0.9600
C11—C121.532 (3)
C1—O1—H1109.5H13B—C13—H13C109.5
C17—O3—C18116.9 (2)C11—C14—H14A109.5
C19—O5—C20116.0 (2)C11—C14—H14B109.5
O1—C1—C6122.37 (18)H14A—C14—H14B109.5
O1—C1—C2115.09 (18)C11—C14—H14C109.5
C6—C1—C2122.54 (18)H14A—C14—H14C109.5
C3—C2—C1116.58 (19)H14B—C14—H14C109.5
C3—C2—C11121.17 (19)C4—C15—C16114.60 (16)
C1—C2—C11122.24 (18)C4—C15—H15A108.6
C4—C3—C2123.3 (2)C16—C15—H15A108.6
C4—C3—H3118.3C4—C15—H15B108.6
C2—C3—H3118.3C16—C15—H15B108.6
C3—C4—C5117.74 (18)H15A—C15—H15B107.6
C3—C4—C15121.09 (18)C17—C16—C19107.60 (18)
C5—C4—C15121.17 (19)C17—C16—C21108.89 (18)
C4—C5—C6122.81 (19)C19—C16—C21109.42 (18)
C4—C5—H5118.6C17—C16—C15109.27 (18)
C6—C5—H5118.6C19—C16—C15108.57 (17)
C5—C6—C1116.93 (18)C21—C16—C15112.95 (18)
C5—C6—C7120.70 (18)O2—C17—O3123.5 (2)
C1—C6—C7122.36 (17)O2—C17—C16126.0 (2)
C8—C7—C10106.65 (18)O3—C17—C16110.5 (2)
C8—C7—C9111.05 (18)O3—C18—H18A109.5
C10—C7—C9106.34 (18)O3—C18—H18B109.5
C8—C7—C6110.73 (17)H18A—C18—H18B109.5
C10—C7—C6111.32 (16)O3—C18—H18C109.5
C9—C7—C6110.59 (17)H18A—C18—H18C109.5
C7—C8—H8A109.5H18B—C18—H18C109.5
C7—C8—H8B109.5O4—C19—O5123.6 (2)
H8A—C8—H8B109.5O4—C19—C16125.9 (2)
C7—C8—H8C109.5O5—C19—C16110.4 (2)
H8A—C8—H8C109.5O5—C20—H20A109.5
H8B—C8—H8C109.5O5—C20—H20B109.5
C7—C9—H9A109.5H20A—C20—H20B109.5
C7—C9—H9B109.5O5—C20—H20C109.5
H9A—C9—H9B109.5H20A—C20—H20C109.5
C7—C9—H9C109.5H20B—C20—H20C109.5
H9A—C9—H9C109.5C22—C21—C16115.95 (19)
H9B—C9—H9C109.5C22—C21—H21A108.3
C7—C10—H10A109.5C16—C21—H21A108.3
C7—C10—H10B109.5C22—C21—H21B108.3
H10A—C10—H10B109.5C16—C21—H21B108.3
C7—C10—H10C109.5H21A—C21—H21B107.4
H10A—C10—H10C109.5C23—C22—C21113.7 (2)
H10B—C10—H10C109.5C23—C22—H22A108.8
C14—C11—C13107.5 (2)C21—C22—H22A108.8
C14—C11—C12106.2 (2)C23—C22—H22B108.8
C13—C11—C12109.5 (2)C21—C22—H22B108.8
C14—C11—C2111.75 (18)H22A—C22—H22B107.7
C13—C11—C2110.30 (19)C22—C23—C24114.8 (3)
C12—C11—C2111.46 (18)C22—C23—H23A108.6
C11—C12—H12A109.5C24—C23—H23A108.6
C11—C12—H12B109.5C22—C23—H23B108.6
H12A—C12—H12B109.5C24—C23—H23B108.6
C11—C12—H12C109.5H23A—C23—H23B107.5
H12A—C12—H12C109.5C23—C24—H24A109.5
H12B—C12—H12C109.5C23—C24—H24B109.5
C11—C13—H13A109.5H24A—C24—H24B109.5
C11—C13—H13B109.5C23—C24—H24C109.5
H13A—C13—H13B109.5H24A—C24—H24C109.5
C11—C13—H13C109.5H24B—C24—H24C109.5
H13A—C13—H13C109.5
O1—C1—C2—C3−178.16 (19)C1—C2—C11—C1256.3 (3)
C6—C1—C2—C32.2 (3)C3—C4—C15—C1692.5 (2)
O1—C1—C2—C110.8 (3)C5—C4—C15—C16−88.2 (2)
C6—C1—C2—C11−178.84 (19)C4—C15—C16—C1759.5 (2)
C1—C2—C3—C4−0.3 (3)C4—C15—C16—C19176.56 (18)
C11—C2—C3—C4−179.3 (2)C4—C15—C16—C21−61.9 (2)
C2—C3—C4—C5−0.6 (3)C18—O3—C17—O20.4 (3)
C2—C3—C4—C15178.8 (2)C18—O3—C17—C16−178.90 (19)
C3—C4—C5—C6−0.5 (3)C19—C16—C17—O2126.1 (2)
C15—C4—C5—C6−179.80 (19)C21—C16—C17—O27.6 (3)
C4—C5—C6—C12.2 (3)C15—C16—C17—O2−116.2 (3)
C4—C5—C6—C7−179.01 (19)C19—C16—C17—O3−54.6 (2)
O1—C1—C6—C5177.25 (19)C21—C16—C17—O3−173.07 (18)
C2—C1—C6—C5−3.1 (3)C15—C16—C17—O363.1 (2)
O1—C1—C6—C7−1.5 (3)C20—O5—C19—O4−3.3 (4)
C2—C1—C6—C7178.14 (19)C20—O5—C19—C16177.3 (2)
C5—C6—C7—C8−113.8 (2)C17—C16—C19—O4131.7 (3)
C1—C6—C7—C864.8 (2)C21—C16—C19—O4−110.1 (3)
C5—C6—C7—C104.6 (3)C15—C16—C19—O413.6 (3)
C1—C6—C7—C10−176.7 (2)C17—C16—C19—O5−48.9 (3)
C5—C6—C7—C9122.6 (2)C21—C16—C19—O569.3 (2)
C1—C6—C7—C9−58.7 (3)C15—C16—C19—O5−167.05 (19)
C3—C2—C11—C14−6.2 (3)C17—C16—C21—C22169.91 (19)
C1—C2—C11—C14174.9 (2)C19—C16—C21—C2252.6 (3)
C3—C2—C11—C13113.3 (2)C15—C16—C21—C22−68.5 (2)
C1—C2—C11—C13−65.6 (3)C16—C21—C22—C23172.5 (2)
C3—C2—C11—C12−124.8 (2)C21—C22—C23—C24171.4 (2)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O2i0.822.232.832 (2)130
Symmetry codes: (i) −x+1/2, y+1/2, −z+1/2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O2i0.822.232.832 (2)130
Symmetry codes: (i) −x+1/2, y+1/2, −z+1/2.
Acknowledgements top

The authors greatefully acknowledge financial support from the Start Foundation (YT07B14) and the Youth Foundation (YT08Z13) of Yantai University and Yantai Science Development Project (2008302).

references
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