X-ray crystallography of cholest-3,5-diene-7-one
4
1063-7745/05/5003- $26.00 © 2005 Pleiades Publishing, Inc. 0419 Crystallography Reports, Vol. 50, No. 3, 2005, pp. 419–422. From Kristallografiya, Vol. 50, No. 3, 2005, pp. 464–467. Original English Text Copyright © 2005 by Rajnikant, Dinesh, Anshu Sawhney, Mousmi, Shafiullah. 1 INTRODUCTION Steroids perform some of the most fundamental bio- logical functions. They are known to have multifaceted biological properties [1–3]. In continuation of our work on the single-crystal growth of X-ray diffraction quality crystals and crystallographic analysis of steroidal mol- ecules [4–10], the crystal structure of cholest-3,5- diene-7-one is reported in this paper. EXPERIMENTAL The scheme of preparation for the title compound is as follows. A solution of t-butyl chromate [t-butyl alcohol (60 ml), CrO 3 (30 g), acetic acid (84 ml), and acetic anhydride (10 ml)] was added at 0°C to a solution of cholest-5-ene (8 g, 21.62 mmol) in CCl 4 (150 ml), ace- tic acid (30 ml), and acetic anhydride (10 ml). The con- tents were refluxed for 3 h; then they were diluted with water, and the organic layer was washed with a NaHCO 3 solution (15%), water, and dried Na 2 SO 4 . Evaporation of the solvent under reduced pressure pro- vided cholest-3,5-diene-7-one as an oil, which was crystallized from methanol. The solvent loss technique was then employed for the growth of transparent plate- shaped crystals (m.p. = 403 K) using acetone as the sol- vent system. The chemical structure, as shown in Fig. 1, has been assigned on the basis of IR, UV, NMR, and mass spectral data [11]. Three-dimensional crystal intensity data of cholest- 3,5-diene-7-one were obtained from a computer-con- trolled single-crystal X-ray diffractometer (CAD4) [12] using MoK α radiation (λ = 0.71073 Å), and the ϖ-2θ scan mode was employed for data collection. The unit 1 This article was submitted by the authors in English. cell parameters were refined from 25 accurately deter- mined reflections in the range 5.54° to 13.34°. The cell measurement was carried out at 293(2) K and CAD4 programs were used for cell refinement. A total number of 2361 reflections were recorded in the θ range from 2.10° to 24.97°. From the number of reflections recorded, 2361 were found to be unique (with the index range 0 ≤ h ≤ 13, 0 ≤ k ≤ 13, 0 ≤ l ≤ 22) and 1070 were treated as observed [F o > 4σ(F o )]. Two standard reflec- tions (0 9 and 0 1 9) were monitored every 100 reflec- tions to check for crystal deterioration, if any, during beam exposure to the sample. The data were corrected for Lorentz and polarization effects. The crystallo- graphic data are listed in Table 1. Direct methods have been employed for the struc- ture determination by using SHELXS software [13]. All non-hydrogen atoms of the molecule were obtained from the E map. Refinement of the structure was car- ried out by the full-matrix least-squares method using the SHELXL93 program [14]. All the non-hydrogen atoms were refined anisotropically. The hydrogen atoms were fixed stereochemically. Further refinement converged the final R-factor to 0.054. 1 X-ray Crystallography of Cholest-3,5-Diene-7-One 1 Rajnikant*, Dinesh*, Anshu Sawhney*, Mousmi*, and Shafiullah** * Condensed Matter Physics Group, Post Graduate Department of Physics, University of Jammu, Jammu Tawi, 180006 India e-mail: [email protected] ** Department of Chemistry, Aligarh Muslim University, Aligarh, India Received October 3, 2003 Abstract—The molecular structure of cholest-3,5-diene-7-one (C 27 H 42 O) is determined by X-ray diffraction. The compound crystallizes in the orthorhombic crystal system (space group P2 1 2 1 2 1 ) with unit cell parameters a = 11.281(5) Å, b = 11.350(5) Å, c = 18.518(5) Å, and Z = 4. The structure is solved by direct methods and refined to an R-value of 0.054 for 1070 observed reflections [F o > 4σ(F o )]. Ring A adopts a distorted half-chair conformation, ring B exists in sofa conformation, ring C acquires a chair conformation, and the five-membered ring D occurs in distorted half-chair conformation. The crystal structure is stabilized by van der Waals forces. © 2005 Pleiades Publishing, Inc. STRUCTURE OF ORGANIC COMPOUNDS O 1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 A B C D Fig. 1. Chemical structure of cholest-3,5-diene-7-one.
Transcript of X-ray crystallography of cholest-3,5-diene-7-one
Crystallography Reports, Vol. 50, No. 3, 2005, pp. 419–422. From Kristallografiya, Vol. 50, No. 3, 2005, pp. 464–467.Original English Text Copyright © 2005 by Rajnikant, Dinesh, Anshu Sawhney, Mousmi, Shafiullah.
STRUCTUREOF ORGANIC COMPOUNDS
X-ray Crystallography of Cholest-3,5-Diene-7-One1 Rajnikant*, Dinesh*, Anshu Sawhney*, Mousmi*, and Shafiullah**
* Condensed Matter Physics Group, Post Graduate Department of Physics, University of Jammu, Jammu Tawi, 180006 India
e-mail: [email protected]** Department of Chemistry, Aligarh Muslim University, Aligarh, India
Received October 3, 2003
Abstract—The molecular structure of cholest-3,5-diene-7-one (C27H42O) is determined by X-ray diffraction.The compound crystallizes in the orthorhombic crystal system (space group P212121) with unit cell parametersa = 11.281(5) Å, b = 11.350(5) Å, c = 18.518(5) Å, and Z = 4. The structure is solved by direct methods andrefined to an R-value of 0.054 for 1070 observed reflections [Fo > 4σ(Fo)]. Ring A adopts a distorted half-chairconformation, ring B exists in sofa conformation, ring C acquires a chair conformation, and the five-memberedring D occurs in distorted half-chair conformation. The crystal structure is stabilized by van der Waals forces.© 2005 Pleiades Publishing, Inc.
1 INTRODUCTION
Steroids perform some of the most fundamental bio-logical functions. They are known to have multifacetedbiological properties [1–3]. In continuation of our workon the single-crystal growth of X-ray diffraction qualitycrystals and crystallographic analysis of steroidal mol-ecules [4–10], the crystal structure of cholest-3,5-diene-7-one is reported in this paper.
EXPERIMENTAL
The scheme of preparation for the title compound isas follows.
A solution of t-butyl chromate [t-butyl alcohol(60 ml), CrO3 (30 g), acetic acid (84 ml), and aceticanhydride (10 ml)] was added at 0°C to a solution ofcholest-5-ene (8 g, 21.62 mmol) in CCl4 (150 ml), ace-tic acid (30 ml), and acetic anhydride (10 ml). The con-tents were refluxed for 3 h; then they were diluted withwater, and the organic layer was washed with aNaHCO3 solution (15%), water, and dried Na2SO4.Evaporation of the solvent under reduced pressure pro-vided cholest-3,5-diene-7-one as an oil, which wascrystallized from methanol. The solvent loss techniquewas then employed for the growth of transparent plate-shaped crystals (m.p. = 403 K) using acetone as the sol-vent system. The chemical structure, as shown inFig. 1, has been assigned on the basis of IR, UV, NMR,and mass spectral data [11].
Three-dimensional crystal intensity data of cholest-3,5-diene-7-one were obtained from a computer-con-trolled single-crystal X-ray diffractometer (CAD4) [12]using MoKα radiation (λ = 0.71073 Å), and the ω−2θscan mode was employed for data collection. The unit
1 This article was submitted by the authors in English.
1063-7745/05/5003- $26.00 0419
cell parameters were refined from 25 accurately deter-mined reflections in the range 5.54° to 13.34°. The cellmeasurement was carried out at 293(2) K and CAD4programs were used for cell refinement. A total numberof 2361 reflections were recorded in the θ range from2.10° to 24.97°. From the number of reflectionsrecorded, 2361 were found to be unique (with the indexrange 0 ≤ h ≤ 13, 0 ≤ k ≤ 13, 0 ≤ l ≤ 22) and 1070 weretreated as observed [Fo > 4σ(Fo)]. Two standard reflec-
tions (0 9 and 0 1 9) were monitored every 100 reflec-tions to check for crystal deterioration, if any, duringbeam exposure to the sample. The data were correctedfor Lorentz and polarization effects. The crystallo-graphic data are listed in Table 1.
Direct methods have been employed for the struc-ture determination by using SHELXS software [13].All non-hydrogen atoms of the molecule were obtainedfrom the E map. Refinement of the structure was car-ried out by the full-matrix least-squares method usingthe SHELXL93 program [14]. All the non-hydrogenatoms were refined anisotropically. The hydrogenatoms were fixed stereochemically. Further refinementconverged the final R-factor to 0.054.
1
O1
1
2
3
45
67
8
910
11
1213
14 15
16
1718
19
20
21 22
23
2425
26
27
A B
C D
Fig. 1. Chemical structure of cholest-3,5-diene-7-one.
© 2005 Pleiades Publishing, Inc.
420
RAJNIKANT
et al
.
Table 1. Crystal data and structure refinement details
Crystal description Transparent rectangular plates
Chemical formula C27H42O
Molecular weight 382.63
Crystal system, space group Orthorhombic, P212121
Unit cell dimensions a = 11.281(5) Å, b = 11.350(5) Å, c = 18.518(5) Å
Volume 2371.0(16) Å3
Z, calculated density 4, 1.077 åg/m3
Radiation, wavelength (λ) MoKα, 0.71073 Å
F(000) 848
Crystal size 0.30 × 0.25 × 0.20 mm
Range θ for data collection 2.10°–24.97°
Limiting indices 0 ≤ h ≤ 13, 0 ≤ k ≤ 13, 0 ≤ l ≤ 22
Reflections collected/unique 2361/2361
Data/restraints/parameters 2361/2/254
Goodness-of-fit on F2 0.847
Final R-factors R1 = 0.054, wR2 = 0.133
Largest diff. peak and hole –0.11 < ∆ρ < 0.23 e Å–3
RESULTS AND DISCUSSION
The final positional and equivalent isotropic dis-placement parameters for all the non-hydrogen atomsare listed in Table 2. Bond distances and bond anglesare presented in Table 3. A general view of the moleculein the atomic numbering scheme (thermal ellipsoids aredrawn at 50% probability) is shown in Fig. 2 [15].
Bond distances and angles are in good agreementwith some analogous structures [4, 9, 16–20] for thevalues in which the atoms C(2), C(3), C(13), C(17),C(20), C(22), C(23) were involved. The disagreementbetween some of the bond distances and angles of thepresent structure with its analogues could be due to thedifference in the nature and position of substituents.The mean bond lengths, C(sp3)–C(sp3) = 1.535(7) Å,C(sp3)–C(sp2) = 1.515(8) Å, C(sp2)–C(sp2) = 1.357(9) Å,and C(sp2)=O = 1.240(7) Å, are also quite close to the
C
standard values [21, 22]. The double bond character ofC(3)=C(4) and C(5)=C(6) are confirmed by their dis-tances of 1.317(10) and 1.332(8) Å, respectively. Theendocyclic bond angles in the steroid nucleus fall in therange from 105.3(4)° to 126.6(5)° [the average valuebeing 114.4(7)°] for the six-membered rings and from100.9(3)° to 107.7(4)° [the average value being103.9(4)°] for the five-membered ring.
The ring A adopts a distorted half-chair conforma-tion with the asymmetry parameter ∆C2 = 9.32 [23].Ring B acquires a sofa conformation with ∆Cs = 3.45.Ring C occupies a chair conformation with ∆C2 = 4.85and ∆Cs = 1.21 [23]. The five-membered ring D occursin a distorted half-chair conformation with asymmetryparameter ∆C2 = 7.03, phase angle of pseudorotation∆ = –4.23°, and maximum angle of torsion ϕm = –45.3°[24]. The methyl carbon C(18) is largely deviatedbelow the mean plane of rings C and D [the deviation
C(2)C(1) C(19)
C(3)
C(4) C(5)
C(6) C(7)
O(1)
C(10)C(9)
C(11)C(12)
C(13)
C(8) C(14)
C(15)C(16)
C(17)
C(23)
C(24)C(27)
C(25)
C(26)C(22)
C(20)
C(21)
C(18)
Fig. 2. General view of cholest-3,5-diene-7-one.
RYSTALLOGRAPHY REPORTS Vol. 50 No. 3 2005
X-RAY CRYSTALLOGRAPHY 421
being –1.763(5) Å], and the methyl carbon C(19) isdeviated above the mean plane of rings A and B [thedeviation being 0.771(5) Å]. Atoms C(18) and C(19)deviate unidirectionally from the mean ABCD plane.This is depicted in Figs. 2 and 3, respectively. The A/Bring junction is quasi-trans, while B/C and C/D aretrans-fused. In view of the nonexistence of any substi-tution at rings A, B, and C, the magnitude of dihedralangles between the plane of rings A and B, B and C, andC and D is not very large. However, the chain of C8H17atoms at the C(17) position of the five-membered ringnormally does not interfere in the conformation of thisring. It is because the group of atoms at C(17) is
Table 2. Atomic coordinates and equivalent isotropic thermalparameters (Å2) for non-hydrogen atoms (e.s.d.’s are given inparentheses)
Atom X Y Z Ueq
O(1) 0.7075(3) 0.4686(3) 0.1861(2) 0.123(1)
C(1) 0.6873(6) 0.8646(4) 0.3579(2) 0.099(2)
C(2) 0.6933(6) 0.8590(5) 0.4406(3) 0.121(2)
C(3) 0.7487(6) 0.7353(8) 0.4605(3) 0.135(2)
C(4) 0.7544(6) 0.6473(6) 0.4142(4) 0.122(2)
C(5) 0.7067(5) 0.6500(4) 0.3440(3) 0.087(2)
C(6) 0.7252(5) 0.5615(5) 0.2965(4) 0.097(2)
C(7) 0.6834(4) 0.5555(4) 0.2240(4) 0.083(2)
C(8) 0.6092(4) 0.6569(3) 0.1964(3) 0.073(1)
C(9) 0.6375(4) 0.7692(3) 0.2384(2) 0.066(1)
C(10) 0.6325(4) 0.7541(4) 0.3205(3) 0.081(1)
C(11) 0.5666(5) 0.8741(4) 0.2089(2) 0.083(1)
C(12) 0.5712(5) 0.8886(3) 0.1278(2) 0.082(2)
C(13) 0.5361(4) 0.7762(4) 0.0893(2) 0.068(1)
C(14) 0.6168(4) 0.6761(3) 0.1151(2) 0.071(1)
C(15) 0.5939(5) 0.5767(4) 0.0621(3) 0.105(2)
C(16) 0.5713(6) 0.6385(4) –0.0099(3) 0.119(2)
C(17) 0.5607(5) 0.7737(4) 0.0052(3) 0.088(2)
C(18) 0.4041(4) 0.7504(5) 0.1033(3) 0.107(2)
C(19) 0.5034(4) 0.7371(5) 0.3479(3) 0.100(2)
C(20) 0.4765(6) 0.8322(5) –0.0457(3) 0.111(2)
C(21) 0.4646(6) 0.9644(5) –0.0325(3) 0.134(2)
C(22) 0.4925(10) 0.8121(8) –0.1314(5) 0.212(4)
C(23) 0.6044(9) 0.8496(9) –0.1505(5) 0.181(3)
C(24) 0.6395(10) 0.8225(10) –0.2288(6) 0.245(5)
C(25) 0.5812(8) 0.8516(7) –0.2919(4) 0.148(3)
C(26) 0.5647(9) 0.9829(8) –0.2937(5) 0.200(4)
C(27) 0.6215(9) 0.7958(8) –0.3562(5) 0.217(4)
CRYSTALLOGRAPHY REPORTS Vol. 50 No. 3 200
Table 3. Bond distances (Å) and bond angles (deg) for non-hydrogen atoms (e.s.d.’s are given in parentheses)
C(1)–C(2) 1.534(6) C(12)–C(13) 1.513(5)
C(1)–C(10) 1.561(6) C(13)–C(14) 1.533(5)
C(2)–C(3) 1.580(8) C(13)–C(18) 1.539(6)
C(3)–C(4) 1.318(8) C(13)–C(17) 1.581(6)
C(4)–C(5) 1.406(7) C(14)–C(15) 1.517(6)
C(5)–C(6) 1.352(6) C(15)–C(16) 1.529(7)
C(5)–C(10) 1.512(6) C(16)–C(17) 1.564(7)
C(6)–C(7) 1.424(7) C(17)–C(20) 1.494(7)
C(7)–O(1) 1.241(5) C(20)–C(21) 1.526(6)
C(7)–C(8) 1.512(6) C(20)–C(22) 1.615(7)
C(8)–C(14) 1.524(6) C(22)–C(23) 1.378(10)
C(8)–C(9) 1.527(5) C(23)–C(24) 1.533(8)
C(9)–C(10) 1.531(6) C(24)–C(25) 1.381(9)
C(9)–C(11) 1.535(5) C(25)–C(27) 1.425(9)
C(10)–C(19) 1.553(6) C(25)–C(26) 1.502(10)
C(11)–C(12) 1.512(5)
C(2)–C(1)–C(10) 115.3(4) C(11)–C(12)–C(13) 111.6(4)
C(1)–C(2)–C(3) 106.7(5) C(12)–C(13)–C(14) 108.8(3)
C(4)–C(3)–C(2) 122.8(5) C(12)–C(13)–C(18) 109.5(4)
C(3)–C(4)–C(5) 124.5(6) C(14)–C(13)–C(18) 112.4(4)
C(6)–C(5)–C(4) 121.7(5) C(12)–C(13)–C(17) 115.7(4)
C(6)–C(5)–C(10) 118.6(5) C(14)–C(13)–C(17) 100.9(4)
C(4)–C(5)–C(10) 119.7(5) C(18)–C(13)–C(17) 109.4(4)
C(5)–C(6)–C(7) 126.7(5) C(15)–C(14)–C(8) 121.5(4)
O(1)–C(7)–C(6) 119.9(5) C(15)–C(14)–C(13) 104.4(4)
O(1)–C(7)–C(8) 122.3(6) C(8)–C(14)–C(13) 112.4(3)
C(6)–C(7)–C(8) 117.8(5) C(14)–C(15)–C(16) 104.5(4)
C(7)–C(8)–C(14) 114.3(4) C(15)–C(16)–C(17) 107.9(4)
C(7)–C(8)–C(9) 110.3(4) C(20)–C(17)–C(16) 111.8(5)
C(14)–C(8)–C(9) 111.8(3) C(20)–C(17)–C(13) 120.0(4)
C(8)–C(9)–C(10) 113.9(3) C(16)–C(17)–C(13) 102.0(4)
C(8)–C(9)–C(11) 111.0(3) C(17)–C(20)–C(21) 113.1(5)
C(10)–C(9)–C(11) 114.9(4) C(17)–C(20)–C(22) 119.1(6)
C(5)–C(10)–C(9) 110.7(4) C(21)–C(20)–C(22) 107.8(6)
C(5)–C(10)–C(19) 109.2(4) C(23)–C(22)–C(20) 108.1(8)
C(9)–C(10)–C(19) 111.9(4) C(22)–C(23)–C(24) 114.7(8)
C(5)–C(10)–C(1) 106.2(4) C(25)–C(24)–C(23) 128.9(9)
C(9)–C(10)–C(1) 109.7(4) C(24)–C(25)–C(27) 116.7(8)
C(19)–C(10)–C(1) 109.0(4) C(24)–C(25)–C(26) 108.4(8)
C(12)–C(11)–C(9) 114.8(4) C(27)–C(25)–C(26) 117.5(8)
5
422 RAJNIKANT et al.
arranged in such a way that the atomic deviations ofindividual atoms provide some kind of balance to thechain. The free rotation of methyl groups, i.e., C(26)and C(27), could also have some kind of steric hin-drances from the neighboring molecules, which mayallow the C8H17 chain to have a linear kind of character.
The packing of the molecules in the unit cell isshown in Fig. 3. The molecules in the unit cell havebeen plotted down the b axis, and they appear to existin reversed orientations. The ring conformations asdemonstrated by individual ring systems are quite dis-tinctively depicted in the molecular packing. The crys-tal structure is stabilized by van der Waals interactions.
ACKNOWLEDGMENTS
The corresponding author (Rajnikant) is grateful tothe Council of Scientific and Industrial Research, New
Fig. 3. Unit-cell molecular packing.
C
Delhi, for the financial support under Projectno. 03(0927)/01/EMR-II.
REFERENCES1. H. G. Williams-Ashman and A. H. Reddi, Annu. Rev.
Physiol. 33, 31 (1971).2. E. V. Jensen and E. R. Desombre, Annu. Rev. Biochem.
41, 203 (1972).3. W. L. Duax, C. M. Weeks, and D. C. Roherer, Topics of
Stereochemistry, Ed. by N. L. Allinger and E. L. Eliel(Wiley, New York, 1976), Vol. 9, p. 271.
4. A. Singh, V. K. Gupta, K. N. Goswami, et al., Mol.Mater. 6, 53 (1996).
5. Rajnikant, V. K. Gupta, J. Firoz, et al., Crystallogr. Rep.45, 785 (2000).
6. Rajnikant, V. K. Gupta, J. Firoz, et al., Crystallogr. Rep.45 (5), 785 (2000).
7. Rajnikant, V. K. Gupta, J. Firoz, et al., Cryst. Res. Tech-nol. 2, 215 (2001).
8. Rajnikant, V. K. Gupta, J. Firoz, et al., Cryst. Res. Tech-nol. 4 (5), 471 (2001).
9. Rajnikant, V. K. Gupta, E. H. Khan, et al., J. Chem.Crystallogr. 32 (9), 325 (2002).
10. Rajnikant, Dinesh, Anshu, and Mousmi, Cryst. Res.Technol. 39 (4), 353 (2004).
11. Shafiullah, private communication (Aligarh MuslimUniv., Aligarh, 2003).
12. Enraf-Nonius CAD4 Software. Version 5.0 (Enraf–Non-ius, Delft, the Netherlands, 1989).
13. G. M. Sheldrick, SHELXS86: Program for the Solutionof Crystal Structures (Univ. of Göttingen, Germany,1986).
14. G. M. Sheldrick, SHELXL93: Program for the Refine-ment of Crystal Structures (Univ. of Göttingen, Ger-many, 1993).
15. L. J. Farrugia, J. Appl. Crystallogr. 30, 565 (1997).16. V. K. Gupta, Rajnikant, K. N. Goswami, and K. K. Bhu-
tani, Cryst. Res. Technol. A 29, 77 (1994).17. V. K. Gupta, K. N. Goswami, K. K. Bhutani, and
R. M. Vaid, Mol. Mater. B 4, 303 (1994).18. V. K. Gupta, Rajnikant, and K. N. Goswami, Acta Crys-
tallogr., Sect. C: Cryst. Struct. Commun. 50, 798 (1994).19. A. Singh, V. K. Gupta, Rajnikant, and K. N. Goswami,
Cryst. Res. Technol. A 29, 837 (1994).20. A. Singh, V. K. Gupta, Rajnikant, et al., Mol. Mater. B 4,
295 (1994).21. L. E. Sutton, Tables of Interatomic Distances and Con-
figuration in Molecules and Ions (Chemical Society,London, 1965), Special Publ. No. 18.
22. L. S. Bartell and R. A. J. Bonham, J. Chem. Phys. 32,824 (1960).
23. W. L. Duax and D. A. Norton, Atlas of Steroid Structure(Plenum, New York, 1975), p. 1.
24. C. Altona, H. J. Geise, and C. Romers, Tetrahedron 24,13 (1968).
RYSTALLOGRAPHY REPORTS Vol. 50 No. 3 2005
![yne, Diene-ene, and Diene-allene [2+2+1] Cycloaddition ...libres.uncg.edu/ir/uncg/f/M_Croatt_Diene_2010.pdf · to produce a metallacyclooctene, which upon reductive elimination would](https://static.fdocuments.us/doc/165x107/5ae76baa7f8b9a29048ec5ef/yne-diene-ene-and-diene-allene-221-cycloaddition-produce-a-metallacyclooctene.jpg)
