A step toward polytwistane: synthesis and characterization of C2-symmetric tritwistane.
Olbrich, Martin; Mayer, Peter; Trauner, Dirk; Organic & biomolecular chemistry 12 (2014) 108–112; doi:10.1039/c3ob42152j

data_7153657
_publ_section_title
;
 A step toward polytwistane: synthesis and characterization of
 C2-symmetric tritwistane.
;
_journal_issue                   1
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              108
_journal_page_last               112
_journal_paper_doi               10.1039/c3ob42152j
_journal_volume                  12
_journal_year                    2014
_chemical_formula_moiety         'C14 H18 Br2'
_chemical_formula_sum            'C14 H18 Br2'
_chemical_formula_weight         346.101
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_Int_Tables_number      14
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_block_code                C14H18Br2_rv142_trauner
_audit_creation_method           'form98_non/compatible with shelxl97-2'
_audit_update_record             25-Apr-13
_cell_angle_alpha                90.00
_cell_angle_beta                 94.731(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   14.3718(4)
_cell_length_b                   6.4978(2)
_cell_length_c                   12.7356(4)
_cell_measurement_reflns_used    127
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      26.5615
_cell_measurement_theta_min      3.6273
_cell_volume                     1185.26(6)
_computing_cell_refinement       'APEX2 v2012.4-3 (Bruker AXS)'
_computing_data_collection       'Bruker Instrument Service v3.0.21'
_computing_data_reduction        'SAINT V8.18C (Bruker AXS Inc., 2011)'
_computing_structure_refinement
;
Sheldrick, G. M. (2008).
<i>Acta Cryst.</i> A<b>64</b>, 112--122.
;
_computing_structure_solution
;
A. Altomare, M. C. Burla, M. Camalli, G. L. Cascarano, C. Giacovazzo, A.
Guagliardi, A. G. G. Moliterni, G. Polidori, R. Spagna: SIR97: a new tool for
crystal structure determination and refinement; J. Appl. Crystallogr. 1999,
32, 115-119.
;
_diffrn_ambient_temperature      100(2)
_diffrn_detector_area_resol_mean 10.4167
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device       'fixed-chi three-circle diffractometer'
_diffrn_measurement_device_type  'Bruker D8Venture'
_diffrn_measurement_method       'mix of phi and omega scans'
_diffrn_radiation_collimation    0.8_mm
_diffrn_radiation_monochromator  'focusing mirrors'
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0451
_diffrn_reflns_av_sigmaI/netI    0.0278
_diffrn_reflns_limit_h_max       19
_diffrn_reflns_limit_h_min       -19
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            22884
_diffrn_reflns_theta_full        28.33
_diffrn_reflns_theta_max         28.41
_diffrn_reflns_theta_min         3.21
_diffrn_source_current           50
_diffrn_source_power             2.5
_diffrn_source_type              'Bruker TXS'
_diffrn_source_voltage           50
_exptl_absorpt_coefficient_mu    6.808
_exptl_absorpt_correction_T_max  0.7457
_exptl_absorpt_correction_T_min  0.6207
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS V2012/1 (Bruker AXS Inc.)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.93956(10)
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             688
_exptl_crystal_size_max          0.167
_exptl_crystal_size_mid          0.097
_exptl_crystal_size_min          0.090
_refine_diff_density_max         0.508
_refine_diff_density_min         -0.342
_refine_diff_density_rms         0.096
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.054
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     145
_refine_ls_number_reflns         2948
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.054
_refine_ls_R_factor_all          0.0334
_refine_ls_R_factor_gt           0.0233
_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^)+(0.0248P)^2^+0.6269P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0491
_refine_ls_wR_factor_ref         0.0520
_reflns_number_gt                2534
_reflns_number_total             2948
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c3ob42152j.txt
_cod_data_source_block           rv142
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               7153657