112
Note
Table 1. Crystal data and structure refinement of
(1R,2R,5R)-2.
– although well defined – disclosed a biological activ-
ity of about 25% of androsterone.
Empirical formula
Formular weight
C18H30O3
294.42
Experimental Section
Crystal system; space group
orthorhombic; P2 2121
1
˚
a = 9.048(2) A
According to a published procedure [7] the (-)-(3R,4R)-
diketone 1 was treated with 13% acetic peracid over night at
40 ◦C, leading to 40% starting material, 12% dilactone, and
46% crude product 2. To our knowledge this means the first
application of a statistical Baeyer-Villiger reaction. Full ex-
perimental details are given in [5]. Boiling of the high melt-
ing diastereomer in ethanol with sulfuric acid transformed it
into the corresponding hydroxy ester. Very short treatment of
this material with CrO3 in acetone [8] resulted in the appro-
priate ester acid with 92% yield. The carboxylic acid func-
tion by introduction of excess diazomethane was transformed
into a diester, followed by protection of the remaining ke-
tone function by means of ethyleneglycol. Now the stage was
set for Dieckmann cyclisation. Subsequent ester decarboxy-
lation (heating in pyridine for 5 h), and deprotection led to
the dihydro derivative of 3.
˚
b = 15.799(3) A
˚
c = 24.331(5) A
3
˚
V = 3478.1(12) A
Formular units per cell, Z
Calculated density, Dx
Crystal size
Absorption coefficient, µ(Cu-Kα )
F(000)
8
1.125 Mg m3
0.15×0.25×0.50 mm3
0.586 mm−1
1296
◦
Θ Range for data collection
Range for hkl
3.34 to 57.53◦
0 – 9, 0 – 17, 0 – 26
2694
2357
7.1
Independent reflections
Reflections with I > 2σ(I)
Data:parameter ratio
Goodness-of-fit on F2
Final R indices [I > 2σ(I)]
R Indices (all data)
1.023
R1 = 0.0442; wR2 = 0.1171
R1 = 0.0502; wR2 = 0.1224
3
˚
Largest diff. peak and hole
0.210 and −0.136 e/A
Crystallographic data of 2 are presented in Table 1. The
intensities of the reflections have been measured at room
temperature with a diffractometer Syntex P21 using mono-
chromatized Cu-Kα radiation and an ω-scan. The structure
has been solved by direct methods [3] and refined in the
usual way [4]. All H atoms have been added in calculated
positions and were included in the refinement in a riding
mode. Positional and atomic displacement parameters have
been deposited with the Cambridge Crystallographic Data
Centre, CCDC-281176. Copies of the data can be obtained
free of charge on application to The Director, CCDC, 12
Union Road, Cambridge CB2 1EZ, UK (Fax: +44 1223
336-033; e-mail for inquiry: data request@ccdc.cam.ac.uk
can be attributed to this structure, since the (3R,4R)
antipode of 1 served as starting material [5, 6]. The
geometry of the two symmetry independent molecules
of the asymmetric unit does not deviate significantly
from averaged values. The rings are connected equa-
torially and reveal a chair conformation. Three weak
hydrogen bonds of the type C-H...O with distances
˚
C...O between 3.322(5) and 3.484(5) A and angles
at the H atom in the range of 147 to 164◦ connect
the molecules. Later on 2 was transformed for phys-
iological assays into the target molecule 3 containing
four contiguous chiral centers, but the separation of
[5] B. Kluess, PhD Thesis, TU Braunschweig, Germany
[1] H. H. Inhoffen, W. Kreiser, N.-J. Myung, Liebigs Ann.
Chem. 739, 108 (1970).
(1973).
[6] T. Sukri, PhD Thesis, TU Braunschweig, Germany
(1973).
[7] P. S. Starcher, B. J. Phillips, J. Am. Chem. Soc. 80,
4079 (1958).
[2] H. H. Inhoffen, D. Kopp, S. Maric, J. Bekurdts, R. Se-
limoglu, Tetrahedron Lett. 11, 999 (1970).
[3] G. M. Sheldrick, SHELXTL-Plus Release 4.21/V,
Siemens Analytical X-ray Instruments Inc., Madison,
Wisconsin, USA (1990).
[8] H. Kiliani, Ber. Dtsch. Chem. Ges. 46, 667 (1913).
[4] G. M. Sheldrick, SHELXL-97, Program for Crystal
Structure Refinement, University of Go¨ttingen, Ger-
many (1997).
Unauthenticated
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