Converting Caffeine to Electronically Different N-Heterocyclic Carbenes with a Hypoxanthine Backbone
Makhloufi, Abdelaziz; Frank, Walter; Ganter, Christian; Organometallics 31 (2012) 7272–; doi:10.1021/om300836w

data_4079563
_publ_section_title
;
 Converting Caffeine to Electronically Different N-Heterocyclic Carbenes
 with a Hypoxanthine Backbone
;
_journal_issue                   20
_journal_name_full               Organometallics
_journal_page_first              7272
_journal_paper_doi               10.1021/om300836w
_journal_volume                  31
_journal_year                    2012
_chemical_formula_moiety         'C18 H26 N8 O2 2+, 2(B F4 1-)'
_chemical_formula_sum            'C18 H26 B2 F8 N8 O2'
_chemical_formula_weight         560.09
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 99.45(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   11.616(2)
_cell_length_b                   9.5970(19)
_cell_length_c                   11.503(2)
_cell_measurement_reflns_used    5448
_cell_measurement_temperature    291(2)
_cell_measurement_theta_max      23.24
_cell_measurement_theta_min      2.19
_cell_volume                     1264.9(4)
_computing_cell_refinement
;
<i>CrysAlis PRO</i>, Ver.1.171.33.52 (Oxford Diffraction Ltd., 2009)
;
_computing_data_collection
;
<i>CrysAlis PRO</i>, Ver.1.171.33.52 (Oxford Diffraction Ltd., 2009)
;
_computing_data_reduction
;
<i>CrysAlis PRO</i>, Ver.1.171.33.52 (Oxford Diffraction Ltd., 2009)
;
_computing_molecular_graphics    'SHELXTL (Sheldrick, 1998)'
_computing_publication_material  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      291(2)
_diffrn_detector_area_resol_mean 32.3
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Xcalibur, Eos'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0000
_diffrn_reflns_av_sigmaI/netI    0.0228
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            15810
_diffrn_reflns_theta_full        24.99
_diffrn_reflns_theta_max         24.99
_diffrn_reflns_theta_min         2.77
_diffrn_standards_decay_%        0
_exptl_absorpt_coefficient_mu    0.138
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.471
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prismatic
_exptl_crystal_F_000             576
_exptl_crystal_size_max          0.5
_exptl_crystal_size_mid          0.45
_exptl_crystal_size_min          0.2
_refine_diff_density_max         0.298
_refine_diff_density_min         -0.233
_refine_diff_density_rms         0.040
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.158
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     206
_refine_ls_number_reflns         15810
_refine_ls_number_restraints     9
_refine_ls_restrained_S_all      1.162
_refine_ls_R_factor_all          0.0890
_refine_ls_R_factor_gt           0.0722
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0269P)^2^+0.6326P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1353
_refine_ls_wR_factor_ref         0.1414
_reflns_number_gt                12721
_reflns_number_total             15810
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            om300836w_si_001.cif
_cod_data_source_block           no_105_compound_13-(BF4)2
_cod_depositor_comments
;
The following automatic conversions were performed:
'_atom_site_symetry_multiplicity' tag replaced with
'_atom_site_symmetry_multiplicity'.

Automatic conversion script
Id: cif_correct_tags 1440 2010-10-19 06:21:57Z saulius 

The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 1891 2012-01-12 08:04:46Z andrius 
;
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               4079563