# CIF-file generated for  S810C  MOKA 60KV150MA LNT MON 210193   

#===============================================================================
data_global
#===============================================================================

# 0. AUDIT DETAILS

_audit_creation_data             03-Aug-93
_audit_creation_method           'PLATON <TABLE ACC> option' 
_audit_update_record            
;
?
;
#===============================================================================

# 1. SUBMISSION DETAILS

_publ_contact_author            # Name and address of author for correspondence
;
 Anthony L. Spek
 Bijvoet Center for Biomolecular Research
 Department of Crystal and Structural Chemistry
 Utrecht University
 Padualaan 8
 3584 CH  Utrecht
 The Netherlands
;
_publ_contact_author_phone       '+31 30 532538'
_publ_contact_author_fax         '+31 30 533940'
_publ_contact_author_email       spea@xray.chem.ruu.nl

_publ_requested_journal          'Acta Crystallographica C' 
_publ_requested_coeditor_name    ?

_publ_contact_letter            
;
Please consider this CIF submission for publication as a
Regular Structure Paper in Acta Crystallographica C. 
;

#===============================================================================

# 2. PROCESSING SUMMARY (JOURNAL OFFICE ONLY)

_journal_date_recd_electronic    ?

_journal_date_to_coeditor        ?
_journal_date_from_coeditor      ?
_journal_date_accepted           ?

_journal_date_printers_first     ?
_journal_date_printers_final     ?
_journal_date_proofs_out         ?
_journal_date_proofs_in          ?

_journal_coeditor_name           ?
_journal_coeditor_code           ?
_journal_coeditor_notes         
; ?
;

_journal_techeditor_code         ?
_journal_techeditor_notes       
; ?
;

_journal_coden_ASTM              ?
_journal_name_full               ?
_journal_year                    ?
_journal_volume                  ?
_journal_issue                   ?
_journal_page_first              ?
_journal_page_last               ?


_journal_suppl_publ_number       ?
_journal_suppl_publ_pages        ?


#===============================================================================

# 3. TITLE AND AUTHOR LIST

_publ_section_title             
;
 Low-temperature structure of bicyclohexylidene
;

# The loop structure below should contain the names and adresses of all
# authors, in the required order of publication. Repeat as necessary.


loop_
_publ_author_name               
_publ_author_address            
'Nora Veldman'
;
 Bijvoet Center for Biomolecular Research
 Department of Crystal and Structural Chemistry
 Utrecht University 
 Padualaan 8
 3584 CH  Utrecht
 The Netherlands
;
'Anthony L. Spek'
;
 Bijvoet Center for Biomolecular Research
 Department of Crystal and Structural Chemistry
 Utrecht University 
 Padualaan 8
 3584 CH  Utrecht
 The Netherlands
;
'Frans J. Hoogesteger'
;
 Debye Institute
 Department of Physical Organic Chemistry
 Utrecht University
 Padualaan 8
 3584 CH  Utrecht
 The Netherlands.
;
'Jan W. Zwikker'
;
 Debye Institute
 Department of Physical Organic Chemistry
 Utrecht University
 Padualaan 8
 3584 CH  Utrecht
 The Netherlands.
;
'Leonardus W. Jenneskens'
;
 Debye Institute
 Department of Physical Organic Chemistry
 Utrecht University
 Padualaan 8
 3584 CH  Utrecht
 The Netherlands.
;

#===============================================================================

# 4. TEXT

_publ_section_abstract 
;  
The two apical Csp₃-Csp₃ bonds (mean 1.521(2)Å) are
significantly shorter than the other two Csp₃-Csp₃ bonds
(mean 1.530(2)Å).
; 
_publ_section_comment 
; 
Well defined oligomers of [1.1.1]propellane (Murthy, Hassenrück,
Lynch & Michl, 1989; Friedli, Lynch, Kaszynski & Michl, 1990;
Kaszynski, McMurdie & Michl, 1991; Kaszynski, Friedli & Michl, 1992)
and bicyclo[2.2.2]octane (Zimmerman, King & Meinhardt, 1992) receive
considerable attention as building blocks for supramolecular
assemblies (Obeng, Laing, Friedli, Yang, Wang, Thulstrup, Bard and
Michl, 1992). Currently, we are developing synthetic strategies for
the preparation of oligo(cyclohexylidenes) [1(n) in scheme 1;
Hoogesteger, Havenith, Zwikker & Jenneskens, 1993], which may be
considered as a new class of molecular building blocks. For synthesis
we are using amongst others a Barton-Kellogg approach (Barton &
Willis, 1972; Buter, Wassenaar & Kellogg, 1972). With respect to their
applicability for the preparation of defined supramolecular
assemblies, our primary object is to gain insight in the solid state
structures of compound 1(n) concomitant with n.  
A room temperature single crystal structure determination for
bicyclohexylidene [1(1)], synthesized by Criegee, Vogel & Horger
(1952), has been reported (Sasvári & Löw, 1965).  
For future reference we report here a more accurate low temperature
study. The molecule is located on a crystallographic centre of
symmmetry. Combined with a noncrystallographic mirror plane
perpendicular to the double-bond plane, this results in an approximate
C₂ₕ symmetry. Bond distances and angles are equal within their
standard deviation.

The bonds around C1 have values in the range expected for 
Csp₂-Csp₂ and Csp₂-Csp₃ bonds. Interestingly, the two 
Csp₃-Csp₃ bonds involving C4 [C3-C4 1.519(2), C4-C5 1.523(3) Å]
are significantly shorter than the other two Csp₃-Csp₃ bonds
[C2-C3 1.531(2), C5-C6 1.529(2) Å].
All bonds are shorter than the standard 1.54 Å. Both semi-emperical
(AMI: Dewar, Zoebisch, Healy & Stewart, 1985) and ab initio (STO-3G, 6-31G: 
Hehre, Radom, von R. Schleyer & Pople, 1986) calculations appear to support
these experimental observations.
Similar effects were reported by Sasvári & Löw (1965) for the room
temperature structure. However, our structure determination does not
support the large difference between the two Csp₂-Csp₃ bond
distances found in the Sasvári & Löw structure.
;
_publ_section_experimental      
;
Crystals used for data collection were obtained by sublimation.
;
_publ_section_references        
; 
 Altomare, A., Cascarano, G., Giacovazzo, C. & Guagliardi, A.
   (1993). J. Appl. Cryst. 26, 343-350.

 Barton, D.H.R. & Willis, B.J. (1972). J. Chem. Soc., Perkin Trans. I,
    305-310.

 Boer, J.L. de & Duisenberg, A.J.M. (1984). Acta Cryst. A40, C410.

 Buter, J., Wassenaar, S. & Kellogg, R.M. (1972). J. Org. Chem. 37, 
    4045-4060.

 Criegee, R., Vogel, E. & Horger, H. (1952). Chem. Ber. 85, 144-152.

 Cromer, D.T. & Mann, J.B. (1968). Acta Cryst. A24, 321-324.

 Dewar, M.J.S., Zoebisch, E.G., Healy, E.F. & Stewart,
    J.J.P. (1985). J. Am. Chem. Soc. 107, 3902-3909.

 Friedli, A.C., Lynch, V.M., Kaszynski, P. & Michl, J. (1990). Acta
    Cryst. B46, 377-389.

 Hehre, W.J., Radom, L., von R. Schleyer, P. & Pople, J.A. (1986).
    Ab Initio molecular Orbital Theory, John Wiley and Sons, Inc.

 Hoogesteger, F.J., Havenith, R.W.A., Zwikker, J.W. & Jenneskens,
    L.W.  (1993).  In preparation.

 Kaszynski, P., McMurdie, N.D. & Michl, J. (1991). J. Org. Chem., 56, 307-316. 

 Kaszynski, P., Friedli, A.C. & Michl, J. (1992). J. Am. Chem. Soc.
    114, 601-620.

 Murthy, G.S., Hassenrück, K., Lynch, V.M. & Michl, J. (1989). J.
    Am. Chem. Soc. 111, 7262-7264. 

 Obeng, Y.S., Laing, M.E., Friedli, A.C., Yang, H.C., Wang, D.,
    Thulstrup, E.W., Bard A.J. & Michl, J. (1992). J. Am. Chem. Soc. 114,
    9943-9952.  

 Sasvári, K. & Löw, M. (1965). Acta Cryst. 19, 840-848.

 Sheldrick, G.M. (1976). SHELX-76. A Program for Crystal
    Structure Determination, Univ. of Cambridge, England.

 Spek, A.L. (1993). Helena, Program for Datareduction, University of
    Utrecht, The Netherlands.

 Spek, A.L.(1990), Acta Cryst., A46, C34.

 Zimmerman, H.E., King, R.K. & Meinhardt, M.B. (1992). J. Org. Chem.
    57, 5484-5492. 
;
_publ_section_figure_captions   
;
Figure 1 Thermal motion ellipsoid plot (50% probalility level)
of bicyclohexylidene.
;
_publ_section_acknowledgements  
; 
This work was supported in part (A.L.S. and N.V.) by the Netherlands
Foundation of Chemical Research (SON) with financial aid from the
Netherlands Organization for Scientific Research (NWO).
;
_publ_section_table_legends  
;
;   
#===============================================================================

data_S810C

#===============================================================================

# 5. CHEMICAL DATA

_chemical_name_systematic       
; 
bicyclohexylidene
;
_chemical_name_common            bicyclohexylidene
_chemical_formula_moiety         'C12 H20'
_chemical_formula_structural     ?
_chemical_formula_analytical     ?
_chemical_formula_sum            'C12 H20'
_chemical_formula_weight         164.29
_chemical_melting_point          348
_chemical_compound_source 
;
'Hoogesteger, Havenith, Zwikker & Jenneskens (1993)'
;

loop_
_atom_type_symbol               
_atom_type_description          
_atom_type_scat_dispersion_real 
_atom_type_scat_dispersion_imag 
_atom_type_scat_source          
 H ? 0 0         'Cromer & Mann (1968)'
 C ? 0.002 0.002 'Cromer & Mann (1968)'

#===============================================================================

# 6. CRYSTAL DATA

_symmetry_cell_setting              Triclinic
_symmetry_space_group_name_H-M   'P -1      '
_symmetry_space_group_name_Hall  ?

loop_
_symmetry_equiv_pos_as_xyz      
 X,Y,Z                         
 -X,-Y,-Z                      

_cell_length_a                       5.2346(6)
_cell_length_b                       6.1700(7)
_cell_length_c                      8.3346(17)
_cell_angle_alpha                   71.831(14)
_cell_angle_beta                    77.530(13)
_cell_angle_gamma                    74.985(9)
_cell_volume                         244.34(7)
_cell_formula_units_Z                        1
_cell_measurement_temperature              150
_cell_measurement_reflns_used               24
_cell_measurement_theta_min                8.8
_cell_measurement_theta_max               16.7
_cell_special_details            
; 
Least squares treatment of 24 SET4 setting angles
;

_exptl_crystal_description       'Transparent needle shaped'
_exptl_crystal_colour            colourless
_exptl_crystal_size_max               0.75
_exptl_crystal_size_mid               0.12
_exptl_crystal_size_min               0.05
_exptl_crystal_density_meas      ?
_exptl_crystal_density_diffrn        1.117
_exptl_crystal_density_method    ?
_exptl_crystal_F_000                    92
_exptl_absorpt_coefficient_mu         0.06
_exptl_crystal_density_meas_temp ?
_exptl_absorpt_correction_type   ?
_exptl_absorpt_correction_T_min  ?
_exptl_absorpt_correction_T_max  ?

#===============================================================================

# 7. EXPERIMENTAL DATA

_exptl_special_details          
; ?
;
_diffrn_ambient_temperature            150
_diffrn_radiation_wavelength       0.71073
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_source         'Enraf Nonius rotating anode'
_diffrn_radiation_monochromator  'graphite'

_diffrn_measurement_device       'Enraf Nonius CAD4-Turbo'
_diffrn_measurement_method       ω/2θ

_diffrn_standards_number         3
_diffrn_standards_interval_count ?
_diffrn_standards_interval_time  60
_diffrn_standards_decay_%        0

loop_
_diffrn_standard_refln_index_h  
_diffrn_standard_refln_index_k  
_diffrn_standard_refln_index_l  
 2 2 6
 0 2 2
 1 5 2

_diffrn_reflns_number            2453  
_diffrn_reflns_av_R_equivalents  0.065 
_diffrn_reflns_av_sigmaI/netI    0.02  
_diffrn_reflns_limit_h_min       -6    
_diffrn_reflns_limit_h_max       6     
_diffrn_reflns_limit_k_min       -7    
_diffrn_reflns_limit_k_max       7     
_diffrn_reflns_limit_l_min       -10   
_diffrn_reflns_limit_l_max       10    
_diffrn_reflns_theta_min         2.6   
_diffrn_reflns_theta_max         27.5  
_diffrn_reflns_reduction_process
;
 ?
;

_reflns_number_total             2453
_reflns_number_observed          793
_reflns_observed_criterion       '> 2.5\s(I)'

_computing_data_collection       'Locally modified CAD4-Version 5 software'
_computing_cell_refinement       'SET4 (de Boer & Duisenberg, 1984)' 
_computing_data_reduction        'HELENA (Spek, 1993)'              
_computing_structure_solution    
;
SIR92 (Altomare, Cascarano, Giacovazzo & Guagliardi, 1993)
;        
_computing_structure_refinement  'SHELX76 (Sheldrick, 1976)'      
_computing_molecular_graphics    'PLATON93 (Spek, 1990)' 
_computing_publication_material  'PLATON93 (Spek, 1990)' 

#===============================================================================

# 8. REFINEMENT DATA

_refine_special_details         
;
 ?
;

_refine_ls_structure_factor_coef F
_refine_ls_matrix_type           full
_refine_ls_weighting_scheme      '1/(\s^2^(F)+0.000936F^2^)'
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   ?
_atom_sites_solution_hydrogens   difmap
_refine_ls_hydrogen_treatment    refxyz
_refine_ls_extinction_method     ?
_refine_ls_extinction_coef       ?
_refine_ls_extinction_expression ?
_refine_ls_abs_structure_details ?
_refine_ls_abs_structure_Flack   ?
_refine_ls_number_reflns         793  
_refine_ls_number_parameters     86   
_refine_ls_number_restraints     ?    
_refine_ls_number_constraints    ?    
_refine_ls_R_factor_all          ?    
_refine_ls_R_factor_obs          0.050
_refine_ls_wR_factor_all         ?    
_refine_ls_wR_factor_obs         0.064
_refine_ls_goodness_of_fit_all   ?
_refine_ls_goodness_of_fit_obs   0.24
_refine_ls_shift/esd_max         0.042 
_refine_ls_shift/esd_mean        0.0079
_refine_diff_density_max         0.42  
_refine_diff_density_min         -0.22 

#===============================================================================

# 9. ATOMIC COORDINATES AND THERMAL PARAMETERS

loop_
_atom_site_label                
_atom_site_thermal_displace_type
_atom_site_fract_x              
_atom_site_fract_y              
_atom_site_fract_z              
_atom_site_occupancy            
_atom_site_U_iso_or_equiv       
 C1      Uani     0.9702(3)    0.5502(3)    0.4208(2)         1   0.0180(5)     
 C2      Uani     0.8563(3)    0.8074(3)    0.3517(2)         1   0.0217(5)     
 C3      Uani     0.5969(3)    0.8486(3)    0.2798(2)         1   0.0228(5)     
 C4      Uani     0.6378(3)    0.7215(3)    0.1439(2)         1   0.0238(5)     
 C5      Uani     0.7469(3)    0.4621(3)    0.2152(2)         1   0.0222(5)     
 C6      Uani     1.0051(3)    0.4211(3)    0.2878(2)         1   0.0213(5)     
 H21     Uiso      0.827(4)     0.887(4)     0.436(2)         1  0.0289(17)     
 H22     Uiso      0.993(4)     0.876(3)     0.252(3)         1  0.0289(17)     
 H31     Uiso      0.530(4)     1.018(4)     0.231(2)         1  0.0289(17)     
 H32     Uiso      0.455(4)     0.793(3)     0.371(2)         1  0.0289(17)     
 H41     Uiso      0.467(4)     0.745(3)     0.099(2)         1  0.0289(17)     
 H42     Uiso      0.769(4)     0.784(3)     0.043(2)         1  0.0289(17)     
 H51     Uiso      0.782(4)     0.379(3)     0.124(3)         1  0.0289(17)     
 H52     Uiso      0.608(4)     0.397(3)     0.308(2)         1  0.0289(17)     
 H61     Uiso      1.068(4)     0.253(4)     0.332(2)         1  0.0289(17)     
 H62     Uiso      1.136(4)     0.475(3)     0.191(2)         1  0.0289(17)     

loop_
_atom_site_aniso_label          
_atom_site_aniso_U_11           
_atom_site_aniso_U_22           
_atom_site_aniso_U_33           
_atom_site_aniso_U_23           
_atom_site_aniso_U_13           
_atom_site_aniso_U_12           
  C1       0.0129(8)  0.0167(8)  0.0256(8)  -0.0077(6)  -0.0030(6)  -0.0025(6)  
  C2       0.0232(9)  0.0160(8)  0.0256(9)  -0.0043(7)  -0.0070(7)  -0.0026(7)  
  C3       0.0202(9)  0.0193(9)  0.0257(9)  -0.0034(7)  -0.0050(7)  -0.0007(7)  
  C4       0.0222(9)  0.0245(9)  0.0229(8)  -0.0021(7)  -0.0078(7)  -0.0036(7)  
  C5       0.0242(9)  0.0219(9)  0.0228(8)  -0.0072(7)  -0.0061(7)  -0.0052(7)  
  C6       0.0203(9)  0.0207(9)  0.0231(8)  -0.0078(7)  -0.0041(7)  -0.0018(7)  

#===============================================================================

# 10. MOLECULAR GEOMETRY

_geom_special_details           
;
Bond distances, angles etc. have been calculated using the
rounded fractional coordinates. All esds are estimated
from the variances of the (full) variance-covariance matrix.
The cell esds are taken into account in the estimation of
distances, angles and torsion angles
;

loop_
_geom_bond_atom_site_label_1    
_geom_bond_atom_site_label_2    
_geom_bond_distance             
_geom_bond_site_symmetry_1      
_geom_bond_site_symmetry_2      
_geom_bond_publ_flag            
 C1      C2         1.514(3)                     .       .                   yes
 C1      C6         1.511(2)                     .       .                   yes
 C1      C1         1.339(2)                     .     2_766                 yes
 C2      C3         1.531(2)                     .       .                   yes
 C3      C4         1.519(2)                     .       .                   yes
 C4      C5         1.523(3)                     .       .                   yes
 C5      C6         1.529(2)                     .       .                   yes
 C2      H21         0.94(2)                     .       .                   no 
 C2      H22         1.03(2)                     .       .                   no 
 C3      H31         0.99(2)                     .       .                   no 
 C3      H32       0.986(19)                     .       .                   no 
 C4      H41         1.00(2)                     .       .                   no 
 C4      H42       1.007(18)                     .       .                   no 
 C5      H51         1.00(2)                     .       .                   no 
 C5      H52       1.001(19)                     .       .                   no 
 C6      H61         0.98(2)                     .       .                   no 
 C6      H62       0.971(18)                     .       .                   no 

loop_
_geom_angle_atom_site_label_1   
_geom_angle_atom_site_label_2   
_geom_angle_atom_site_label_3   
_geom_angle                     
_geom_angle_site_symmetry_1     
_geom_angle_site_symmetry_2     
_geom_angle_site_symmetry_3     
_geom_angle_publ_flag           
 C2      C1      C6       111.04(13)             .       .       .           yes
 C1      C1      C2       124.55(16)           2_766     .       .           yes
 C1      C1      C6       124.40(17)           2_766     .       .           yes
 C1      C2      C3       111.88(15)             .       .       .           yes
 C2      C3      C4       111.17(14)             .       .       .           yes
 C3      C4      C5       110.42(13)             .       .       .           yes
 C4      C5      C6       111.08(14)             .       .       .           yes
 C1      C6      C5       112.27(14)             .       .       .           yes
 C1      C2      H21       111.2(13)             .       .       .           no 
 C1      C2      H22       108.0(11)             .       .       .           no 
 C3      C2      H21       110.0(14)             .       .       .           no 
 C3      C2      H22       107.0(13)             .       .       .           no 
 H21     C2      H22       108.6(17)             .       .       .           no 
 C2      C3      H31       110.4(13)             .       .       .           no 
 C2      C3      H32       110.8(11)             .       .       .           no 
 C4      C3      H31       109.7(10)             .       .       .           no 
 C4      C3      H32       108.2(11)             .       .       .           no 
 H31     C3      H32       106.5(16)             .       .       .           no 
 C3      C4      H41       111.2(10)             .       .       .           no 
 C3      C4      H42       110.8(11)             .       .       .           no 
 C5      C4      H41       109.9(11)             .       .       .           no 
 C5      C4      H42       108.1(11)             .       .       .           no 
 H41     C4      H42       106.3(15)             .       .       .           no 
 C4      C5      H51       110.5(12)             .       .       .           no 
 C4      C5      H52       108.0(11)             .       .       .           no 
 C6      C5      H51       109.3(13)             .       .       .           no 
 C6      C5      H52       109.5(11)             .       .       .           no 
 H51     C5      H52       108.3(16)             .       .       .           no 
 C1      C6      H61       112.4(10)             .       .       .           no 
 C1      C6      H62       110.7(11)             .       .       .           no 
 C5      C6      H61       108.4(13)             .       .       .           no 
 C5      C6      H62       105.9(12)             .       .       .           no 
 H61     C6      H62       106.9(16)             .       .       .           no 

loop_
_geom_torsion_atom_site_label_1 
_geom_torsion_atom_site_label_2 
_geom_torsion_atom_site_label_3 
_geom_torsion_atom_site_label_4 
_geom_torsion                   
_geom_torsion_site_symmetry_1   
_geom_torsion_site_symmetry_2   
_geom_torsion_site_symmetry_3   
_geom_torsion_site_symmetry_4   
_geom_torsion_publ_flag         
 C6      C1      C2      C3        54.01(18)     .       .       .       .   no 
 C1      C1      C2      C3      -125.40(18)   2_766     .       .       .   no 
 C2      C1      C6      C5       -53.94(18)     .       .       .       .   no 
 C1      C1      C6      C5       125.47(18)   2_766     .       .       .   no 
 C2      C1      C1      C2         180.0(6)     .       .     2_766   2_766 no 
 C2      C1      C1      C6          -0.7(3)     .       .     2_766   2_766 no 
 C6      C1      C1      C2           0.7(3)     .       .     2_766   2_766 no 
 C6      C1      C1      C6        180.00(1)     .       .     2_766   2_766 no 
 C1      C2      C3      C4       -55.73(18)     .       .       .       .   no 
 C2      C3      C4      C5        56.21(18)     .       .       .       .   no 
 C3      C4      C5      C6       -55.88(17)     .       .       .       .   no 
 C4      C5      C6      C1        55.26(18)     .       .       .       .   no 

# End of Crystallographic Information File























