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Volume 69 
Part 7 
Page o1028  
July 2013  

Received 15 May 2013
Accepted 28 May 2013
Online 8 June 2013

Key indicators
Single-crystal X-ray study
T = 194 K
Mean [sigma](C-C) = 0.008 Å
R = 0.069
wR = 0.138
Data-to-parameter ratio = 10.2
Details
Open access

5-[(1R,2R,4R)-2-Methoxy-1,7,7-trimethylbicyclo[2.2.1]hept-2-yl]-1H-tetrazole

aInstitut für Organische Chemie und Chemische Biologie, Universität Frankfurt, Max-von-Laue-Strasse 7, D-60438 Frankfurt am Main, Germany
Correspondence e-mail: bats@chemie.uni-frankfurt.de

The title compound, C12H20N4O, undergoes a phase transition on cooling. The room-temperature structure is tetragonal (P43212, Z' = 1), with the methoxybornyl group being extremely disordered. Below 213 K the structure is orthorhombic (P212121, Z' = 2), with ordered molecules. The two independent molecules (A and B) have very similar conformations; significant differences only occur for the torsion angles about the Cbornyl-Ctetrazole bonds. The independent molecules are approximately related by the pseudo-symmetry relation: xB = -1/4 + yA, yB = 3/4 - xA and zB = 1/4 + zA. In the crystal, molecules are connected by N-H...N hydrogen bonds between the tetrazole groups, forming a pseudo-43 helix parallel to the c-axis direction. The crystal studied was a merohedral twin with a refined twin fraction value of 0.231 (2).

Related literature

For the chemical background and synthesis of the title compound, see: Schell & Engels (1997[Schell, P. & Engels, J. W. (1997). Nucleosides Nucleotides, 16, 769-772.], 1998[Schell, P. & Engels, J. W. (1998). Tetrahedron Lett. 39, 8629-8632.]). For related structures, see: Ohno et al. (1999[Ohno, Y., Akutsu, Y., Arai, M., Tamura, M. & Matsunaga, T. (1999). Acta Cryst. C55, 1014-1016.]).

[Scheme 1]

Experimental

Crystal data
  • C12H20N4O

  • Mr = 236.32

  • Orthorhombic, P 21 21 21

  • a = 13.298 (3) Å

  • b = 13.608 (4) Å

  • c = 14.356 (3) Å

  • V = 2597.9 (11) Å3

  • Z = 8

  • Mo K[alpha] radiation

  • [mu] = 0.08 mm-1

  • T = 194 K

  • 0.65 × 0.24 × 0.20 mm

Data collection
  • Siemens SMART 1K CCD diffractometer

  • 31860 measured reflections

  • 3283 independent reflections

  • 2259 reflections with I > 2[sigma](I)

  • Rint = 0.109

Refinement
  • R[F2 > 2[sigma](F2)] = 0.069

  • wR(F2) = 0.138

  • S = 1.08

  • 3283 reflections

  • 322 parameters

  • 2 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • [Delta][rho]max = 0.20 e Å-3

  • [Delta][rho]min = -0.21 e Å-3

Table 1
Hydrogen-bond geometry (Å, °)

D-H...A D-H H...A D...A D-H...A
N1-H1A...N7 0.88 (1) 2.09 (3) 2.850 (6) 144 (5)
N5-H5C...N3i 0.88 (1) 2.02 (2) 2.857 (6) 160 (5)
Symmetry code: (i) [-x+{\script{1\over 2}}, -y+1, z+{\script{1\over 2}}].

Data collection: SMART (Siemens, 1995[Siemens (1995). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); cell refinement: SMART; data reduction: SAINT (Siemens, 1995[Siemens (1995). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXL97.


Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: SU2603 ).


References

Ohno, Y., Akutsu, Y., Arai, M., Tamura, M. & Matsunaga, T. (1999). Acta Cryst. C55, 1014-1016.  [CSD] [CrossRef] [IUCr Journals]
Schell, P. & Engels, J. W. (1997). Nucleosides Nucleotides, 16, 769-772.  [ChemPort]
Schell, P. & Engels, J. W. (1998). Tetrahedron Lett. 39, 8629-8632.  [Web of Science] [CrossRef] [ChemPort]
Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.  [CrossRef] [ChemPort] [IUCr Journals]
Siemens (1995). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.


Acta Cryst (2013). E69, o1028  [ doi:10.1107/S1600536813014700 ]

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