1,4a,7-Trimethyl-7-vinyl-1,2,3,4,4a,4b,5,6,7,9,10,10a-dodeca-hydro-phenanthrene-1-carboxylic acid.

The title compound, pimaric acid, C(20)H(30)O(2), was isolated from a mixture of resin acids. There are three rings in the structure. The two cyclo-hexane rings have classical chair conformations with trans-fused ring junctions. The cyclo-hexene ring appears as a semi-chair.

Related literature

For physical and spectral data relating to pimaric acid, see: Green et al. (1958 ▶); Harris & Sanderson (1948 ▶). For the biological activity of pimaric acid, see: Imaizumi et al. (2002 ▶); Rubio et al. (2005 ▶).

Experimental

Crystal data

C20H30O2

M = 302.44

Orthorhombic,

a = 20.818 (4) Å

b = 10.990 (2) Å

c = 7.7650 (16) Å

V = 1776.6 (6) Å3

Z = 4

Mo Kα radiation

μ = 0.07 mm−1

T = 293 K

0.30 × 0.20 × 0.10 mm

Data collection

Enraf–Nonius CAD-4 diffractometer

Absorption correction: ψ scan (North et al., 1968 ▶) T min = 0.979, T max = 0.993

1862 measured reflections

1862 independent reflections

1231 reflections with I > 2σ(I)

3 standard reflections every 200 reflections intensity decay: 1%

Refinement

R[F 2 > 2σ(F 2)] = 0.065

wR(F 2) = 0.188

S = 1.00

1862 reflections

193 parameters

H-atom parameters constrained

Δρmax = 0.16 e Å−3

Δρmin = −0.17 e Å−3

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, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXL97.

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809013233/at2757sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809013233/at2757Isup2.hkl

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

C20H30O2	Dx = 1.131 Mg m−3
Mr = 302.44	Melting point: 490K K
Orthorhombic, P21212	Mo Kα radiation, λ = 0.71073 Å
a = 20.818 (4) Å	Cell parameters from 25 reflections
b = 10.990 (2) Å	θ = 9–12°
c = 7.7650 (16) Å	µ = 0.07 mm−1
V = 1776.6 (6) Å3	T = 293 K
Z = 4	Rectangular plate, colorless
F(000) = 664	0.30 × 0.20 × 0.10 mm

Enraf–Nonius CAD-4 diffractometer	1231 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.0000
graphite	θmax = 25.3°, θmin = 2.0°
ω/2θ scans	h = 0→25
Absorption correction: ψ scan (North et al., 1968)	k = 0→13
Tmin = 0.979, Tmax = 0.993	l = −9→9
1862 measured reflections	3 standard reflections every 200 reflections
1862 independent reflections	intensity decay: 1%

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)] = 0.065	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.188	H-atom parameters constrained
S = 1.00	w = 1/[σ2(Fo2) + (0.1P)2 + 0.6P] where P = (Fo2 + 2Fc2)/3
1862 reflections	(Δ/σ)max < 0.001
193 parameters	Δρmax = 0.16 e Å−3
0 restraints	Δρmin = −0.17 e Å−3

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.

	x	y	z	Uiso*/Ueq
O1	0.99697 (17)	0.6536 (3)	0.9540 (7)	0.1009 (15)
O2	0.91875 (17)	0.5243 (3)	0.9640 (8)	0.1170 (19)
H2B	0.9493	0.4772	0.9603	0.176*
C1	0.5623 (5)	0.9204 (9)	0.5670 (15)	0.149 (4)
H1A	0.5421	0.9085	0.6725	0.179*
H1B	0.5589	0.9950	0.5113	0.179*
C2	0.5940 (4)	0.8361 (8)	0.5000 (12)	0.119 (3)
H2A	0.6125	0.8558	0.3947	0.143*
C3	0.5645 (3)	0.6180 (8)	0.4461 (11)	0.124 (3)
H3A	0.5725	0.6340	0.3264	0.186*
H3B	0.5200	0.6321	0.4713	0.186*
H3C	0.5752	0.5350	0.4715	0.186*
C4	0.6077 (3)	0.7061 (6)	0.5606 (8)	0.0801 (17)
C5	0.6758 (2)	0.6766 (5)	0.5262 (7)	0.0711 (14)
H5A	0.6874	0.6647	0.4118	0.085*
C6	0.7215 (2)	0.6657 (4)	0.6420 (6)	0.0521 (11)
C7	0.7116 (2)	0.6929 (4)	0.8315 (6)	0.0498 (11)
H7A	0.7139	0.6144	0.8911	0.060*
C8	0.6445 (2)	0.7431 (5)	0.8672 (7)	0.0680 (14)
H8A	0.6339	0.7301	0.9874	0.082*
H8B	0.6442	0.8300	0.8458	0.082*
C9	0.5940 (2)	0.6822 (6)	0.7544 (8)	0.0787 (16)
H9A	0.5518	0.7136	0.7837	0.094*
H9B	0.5940	0.5952	0.7760	0.094*
C10	0.7870 (2)	0.6163 (5)	0.5973 (6)	0.0640 (13)
H10A	0.7920	0.6179	0.4731	0.077*
H10B	0.7892	0.5320	0.6338	0.077*
C11	0.8424 (2)	0.6850 (5)	0.6776 (6)	0.0577 (12)
H11A	0.8465	0.7645	0.6245	0.069*
H11B	0.8822	0.6409	0.6592	0.069*
C12	0.82995 (19)	0.6994 (4)	0.8726 (5)	0.0445 (10)
H12A	0.8203	0.6169	0.9128	0.053*
C13	0.7675 (2)	0.7720 (4)	0.9057 (5)	0.0484 (11)
C14	0.8910 (2)	0.7370 (4)	0.9743 (6)	0.0532 (12)
C15	0.8742 (3)	0.7497 (5)	1.1667 (7)	0.0662 (14)
H15A	0.8647	0.6699	1.2137	0.079*
H15B	0.9110	0.7821	1.2280	0.079*
C16	0.8169 (3)	0.8327 (5)	1.1954 (7)	0.0697 (14)
H16A	0.8081	0.8385	1.3178	0.084*
H16B	0.8270	0.9137	1.1535	0.084*
C17	0.7580 (2)	0.7849 (5)	1.1030 (5)	0.0562 (13)
H17A	0.7224	0.8396	1.1244	0.067*
H17B	0.7469	0.7061	1.1505	0.067*
C18	0.7663 (2)	0.8972 (4)	0.8218 (7)	0.0620 (13)
H18A	0.8006	0.9458	0.8672	0.093*
H18B	0.7260	0.9360	0.8456	0.093*
H18C	0.7715	0.8887	0.6995	0.093*
C19	0.9237 (2)	0.8539 (5)	0.9099 (8)	0.0758 (16)
H19A	0.9608	0.8706	0.9794	0.114*
H19B	0.8941	0.9206	0.9181	0.114*
H19C	0.9366	0.8435	0.7922	0.114*
C20	0.9393 (2)	0.6334 (4)	0.9643 (7)	0.062

	U11	U22	U33	U12	U13	U23
O1	0.0487 (19)	0.069 (2)	0.185 (4)	0.0073 (17)	−0.008 (3)	−0.014 (3)
O2	0.065 (2)	0.063 (2)	0.223 (6)	0.0112 (18)	−0.001 (3)	0.030 (3)
C1	0.150 (8)	0.132 (7)	0.166 (10)	0.000 (6)	−0.001 (8)	0.027 (7)
C2	0.098 (5)	0.129 (7)	0.130 (7)	0.024 (5)	−0.018 (5)	0.027 (6)
C3	0.090 (5)	0.158 (7)	0.124 (6)	−0.019 (5)	−0.015 (5)	−0.021 (6)
C4	0.056 (3)	0.104 (5)	0.080 (4)	0.003 (3)	−0.012 (3)	−0.004 (4)
C5	0.065 (3)	0.086 (4)	0.062 (3)	0.001 (3)	0.007 (3)	−0.009 (3)
C6	0.056 (3)	0.049 (2)	0.051 (3)	0.000 (2)	0.004 (2)	−0.009 (2)
C7	0.050 (3)	0.052 (3)	0.048 (2)	0.007 (2)	0.010 (2)	0.007 (2)
C8	0.049 (3)	0.088 (3)	0.067 (3)	0.012 (3)	0.004 (3)	−0.003 (3)
C9	0.053 (3)	0.084 (4)	0.100 (4)	0.003 (3)	0.004 (3)	0.008 (4)
C10	0.064 (3)	0.076 (3)	0.052 (3)	0.008 (3)	0.008 (2)	−0.013 (3)
C11	0.051 (3)	0.069 (3)	0.053 (3)	0.010 (2)	0.014 (2)	−0.002 (3)
C12	0.049 (2)	0.042 (2)	0.042 (2)	0.0070 (19)	0.007 (2)	0.005 (2)
C13	0.055 (2)	0.050 (2)	0.041 (2)	0.013 (2)	0.004 (2)	0.001 (2)
C14	0.052 (2)	0.045 (2)	0.063 (3)	0.002 (2)	−0.004 (2)	0.006 (2)
C15	0.071 (3)	0.070 (3)	0.057 (3)	0.016 (3)	−0.011 (3)	0.000 (3)
C16	0.089 (4)	0.069 (3)	0.052 (3)	0.017 (3)	−0.009 (3)	−0.008 (3)
C17	0.068 (3)	0.059 (3)	0.042 (3)	0.016 (2)	0.001 (2)	−0.004 (2)
C18	0.073 (3)	0.051 (3)	0.062 (3)	0.010 (2)	−0.006 (3)	0.007 (2)
C19	0.070 (3)	0.065 (3)	0.093 (4)	−0.013 (3)	−0.021 (3)	0.011 (3)
C20	0.068	0.053	0.064	−0.002	−0.007	0.008

O1—C20	1.223 (6)	C10—H10A	0.9700
O2—C20	1.273 (6)	C10—H10B	0.9700
O2—H2B	0.8200	C11—C12	1.544 (6)
C1—C2	1.251 (11)	C11—H11A	0.9700
C1—H1A	0.9300	C11—H11B	0.9700
C1—H1B	0.9300	C12—C13	1.546 (6)
C2—C4	1.531 (10)	C12—C14	1.552 (6)
C2—H2A	0.9300	C12—H12A	0.9800
C3—C4	1.592 (9)	C13—C18	1.523 (6)
C3—H3A	0.9600	C13—C17	1.551 (6)
C3—H3B	0.9600	C14—C20	1.520 (6)
C3—H3C	0.9600	C14—C19	1.538 (6)
C4—C5	1.479 (7)	C14—C15	1.541 (7)
C4—C9	1.554 (8)	C15—C16	1.517 (7)
C5—C6	1.315 (6)	C15—H15A	0.9700
C5—H5A	0.9300	C15—H15B	0.9700
C6—C10	1.507 (6)	C16—C17	1.515 (7)
C6—C7	1.516 (6)	C16—H16A	0.9700
C7—C8	1.527 (6)	C16—H16B	0.9700
C7—C13	1.563 (6)	C17—H17A	0.9700
C7—H7A	0.9800	C17—H17B	0.9700
C8—C9	1.524 (7)	C18—H18A	0.9600
C8—H8A	0.9700	C18—H18B	0.9600
C8—H8B	0.9700	C18—H18C	0.9600
C9—H9A	0.9700	C19—H19A	0.9600
C9—H9B	0.9700	C19—H19B	0.9600
C10—C11	1.514 (7)	C19—H19C	0.9600
C20—O2—H2B	109.5	C12—C11—H11B	109.9
C2—C1—H1A	120.0	H11A—C11—H11B	108.3
C2—C1—H1B	120.0	C11—C12—C13	110.9 (3)
H1A—C1—H1B	120.0	C11—C12—C14	112.8 (4)
C1—C2—C4	131.5 (10)	C13—C12—C14	117.8 (3)
C1—C2—H2A	114.3	C11—C12—H12A	104.6
C4—C2—H2A	114.3	C13—C12—H12A	104.6
C4—C3—H3A	109.5	C14—C12—H12A	104.6
C4—C3—H3B	109.5	C18—C13—C12	114.1 (4)
H3A—C3—H3B	109.5	C18—C13—C17	109.7 (4)
C4—C3—H3C	109.5	C12—C13—C17	108.6 (4)
H3A—C3—H3C	109.5	C18—C13—C7	109.4 (4)
H3B—C3—H3C	109.5	C12—C13—C7	106.2 (3)
C5—C4—C2	109.1 (6)	C17—C13—C7	108.7 (4)
C5—C4—C9	108.3 (5)	C20—C14—C19	108.4 (4)
C2—C4—C9	114.9 (6)	C20—C14—C15	105.6 (4)
C5—C4—C3	107.9 (5)	C19—C14—C15	109.9 (4)
C2—C4—C3	106.9 (6)	C20—C14—C12	108.5 (4)
C9—C4—C3	109.5 (6)	C19—C14—C12	114.8 (4)
C6—C5—C4	126.2 (5)	C15—C14—C12	109.3 (4)
C6—C5—H5A	116.9	C16—C15—C14	112.1 (4)
C4—C5—H5A	116.9	C16—C15—H15A	109.2
C5—C6—C10	122.0 (4)	C14—C15—H15A	109.2
C5—C6—C7	123.1 (4)	C16—C15—H15B	109.2
C10—C6—C7	114.7 (4)	C14—C15—H15B	109.2
C6—C7—C8	111.8 (4)	H15A—C15—H15B	107.9
C6—C7—C13	111.4 (4)	C17—C16—C15	111.0 (4)
C8—C7—C13	114.4 (4)	C17—C16—H16A	109.4
C6—C7—H7A	106.2	C15—C16—H16A	109.4
C8—C7—H7A	106.2	C17—C16—H16B	109.4
C13—C7—H7A	106.2	C15—C16—H16B	109.4
C9—C8—C7	111.6 (4)	H16A—C16—H16B	108.0
C9—C8—H8A	109.3	C16—C17—C13	113.4 (4)
C7—C8—H8A	109.3	C16—C17—H17A	108.9
C9—C8—H8B	109.3	C13—C17—H17A	108.9
C7—C8—H8B	109.3	C16—C17—H17B	108.9
H8A—C8—H8B	108.0	C13—C17—H17B	108.9
C8—C9—C4	110.8 (5)	H17A—C17—H17B	107.7
C8—C9—H9A	109.5	C13—C18—H18A	109.5
C4—C9—H9A	109.5	C13—C18—H18B	109.5
C8—C9—H9B	109.5	H18A—C18—H18B	109.5
C4—C9—H9B	109.5	C13—C18—H18C	109.5
H9A—C9—H9B	108.1	H18A—C18—H18C	109.5
C6—C10—C11	114.5 (4)	H18B—C18—H18C	109.5
C6—C10—H10A	108.6	C14—C19—H19A	109.5
C11—C10—H10A	108.6	C14—C19—H19B	109.5
C6—C10—H10B	108.6	H19A—C19—H19B	109.5
C11—C10—H10B	108.6	C14—C19—H19C	109.5
H10A—C10—H10B	107.6	H19A—C19—H19C	109.5
C10—C11—C12	109.1 (4)	H19B—C19—H19C	109.5
C10—C11—H11A	109.9	O1—C20—O2	120.0 (5)
C12—C11—H11A	109.9	O1—C20—C14	121.1 (4)
C10—C11—H11B	109.9	O2—C20—C14	118.8 (4)
C1—C2—C4—C5	−138.0 (10)	C14—C12—C13—C7	−163.7 (4)
C1—C2—C4—C9	−16.1 (13)	C6—C7—C13—C18	66.0 (5)
C1—C2—C4—C3	105.6 (12)	C8—C7—C13—C18	−62.1 (5)
C2—C4—C5—C6	108.1 (7)	C6—C7—C13—C12	−57.6 (4)
C9—C4—C5—C6	−17.6 (9)	C8—C7—C13—C12	174.3 (4)
C3—C4—C5—C6	−136.1 (6)	C6—C7—C13—C17	−174.2 (4)
C4—C5—C6—C10	170.2 (5)	C8—C7—C13—C17	57.7 (5)
C4—C5—C6—C7	−5.4 (9)	C11—C12—C14—C20	−65.6 (5)
C5—C6—C7—C8	−4.4 (7)	C13—C12—C14—C20	163.0 (4)
C10—C6—C7—C8	179.7 (4)	C11—C12—C14—C19	55.8 (5)
C5—C6—C7—C13	−133.9 (5)	C13—C12—C14—C19	−75.5 (5)
C10—C6—C7—C13	50.2 (5)	C11—C12—C14—C15	179.8 (4)
C6—C7—C8—C9	37.2 (6)	C13—C12—C14—C15	48.4 (5)
C13—C7—C8—C9	165.1 (4)	C20—C14—C15—C16	−168.9 (4)
C7—C8—C9—C4	−61.6 (6)	C19—C14—C15—C16	74.3 (5)
C5—C4—C9—C8	49.7 (7)	C12—C14—C15—C16	−52.4 (6)
C2—C4—C9—C8	−72.5 (6)	C14—C15—C16—C17	59.3 (6)
C3—C4—C9—C8	167.2 (5)	C15—C16—C17—C13	−58.9 (6)
C5—C6—C10—C11	137.5 (5)	C18—C13—C17—C16	−74.5 (5)
C7—C6—C10—C11	−46.6 (6)	C12—C13—C17—C16	50.8 (5)
C6—C10—C11—C12	50.2 (6)	C7—C13—C17—C16	165.9 (4)
C10—C11—C12—C13	−60.7 (5)	C19—C14—C20—O1	18.5 (7)
C10—C11—C12—C14	164.6 (4)	C15—C14—C20—O1	−99.2 (6)
C11—C12—C13—C18	−56.5 (5)	C12—C14—C20—O1	143.8 (5)
C14—C12—C13—C18	75.7 (5)	C19—C14—C20—O2	−160.4 (5)
C11—C12—C13—C17	−179.2 (4)	C15—C14—C20—O2	81.9 (6)
C14—C12—C13—C17	−47.0 (5)	C12—C14—C20—O2	−35.2 (7)
C11—C12—C13—C7	64.1 (4)