One-pot access to push-pull oligoenes by sequential [2 + 2] cycloaddition-retroelectrocyclization reactions.
Jayamurugan, Govindasamy; Finke, Aaron D.; Gisselbrecht, Jean-Paul; Boudon, Corinne; Schweizer, W. Bernd; Diederich, François; The Journal of organic chemistry 79 (2014) 426–431; doi:10.1021/jo402440m

data_4029094
_publ_section_title
;
 One-pot access to push-pull oligoenes by sequential [2 + 2]
 cycloaddition-retroelectrocyclization reactions.
;
_journal_issue                   1
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              426
_journal_page_last               431
_journal_paper_doi               10.1021/jo402440m
_journal_volume                  79
_journal_year                    2014
_chemical_compound_source        'LOC ETH Zurich'
_chemical_formula_moiety         'C26 H22 N6 '
_chemical_formula_sum            'C26 H22 N6'
_chemical_formula_weight         418.504
_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_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           maXus
_cell_angle_alpha                90.00
_cell_angle_beta                 118.198(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   12.9058(13)
_cell_length_b                   7.5529(7)
_cell_length_c                   12.7458(10)
_cell_measurement_reflns_used    2539
_cell_measurement_temperature    123
_cell_measurement_theta_max      26.022
_cell_measurement_theta_min      2.753
_cell_volume                     1094.96(18)
_computing_cell_refinement       'HKL Scalepack (Otwinowski & Minor 1997)'
_computing_data_collection       KappaCCD
_computing_data_reduction        'Denzo and Scalepak (Otwinowski & Minor, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      123
_diffrn_measured_fraction_theta_full 0.957
_diffrn_measured_fraction_theta_max 0.957
_diffrn_measurement_device       KappaCCD
_diffrn_measurement_method       CCD
_diffrn_orient_matrix_type       X=UH
_diffrn_orient_matrix_UB_11      0.08359
_diffrn_orient_matrix_UB_12      0.00825
_diffrn_orient_matrix_UB_13      0.02948
_diffrn_orient_matrix_UB_21      0.01752
_diffrn_orient_matrix_UB_22      0.10480
_diffrn_orient_matrix_UB_23      -0.07899
_diffrn_orient_matrix_UB_31      0.01441
_diffrn_orient_matrix_UB_32      0.05065
_diffrn_orient_matrix_UB_33      0.07040
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           ' MoK\a'
_diffrn_radiation_wavelength_id  all
_diffrn_reflns_av_R_equivalents  0.18
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            3689
_diffrn_reflns_theta_full        26.03
_diffrn_reflns_theta_max         26.03
_diffrn_reflns_theta_min         4.11
_exptl_absorpt_coefficient_mu    0.079
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            purple
_exptl_crystal_density_diffrn    1.269
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plae
_exptl_crystal_F_000             440.0
_exptl_crystal_size_max          .09
_exptl_crystal_size_mid          .045
_exptl_crystal_size_min          .009
_refine_diff_density_max         0.266
_refine_diff_density_min         -0.222
_refine_diff_density_rms         0.057
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.891
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     151
_refine_ls_number_reflns         2071
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.891
_refine_ls_R_factor_all          0.1510
_refine_ls_R_factor_gt           0.0670
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+ (0.1000P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1534
_refine_ls_wR_factor_ref         0.1978
_reflns_number_gt                1094
_reflns_number_total             2071
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo402440m_si_002.cif
_cod_data_source_block           3a
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to
/usr/data/users/saulius/automatic-downloads/current/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 2281 2013-09-26 08:29:07Z andrius 
;
_cod_original_cell_volume        1095.0(2)
_cod_original_sg_symbol_H-M      'P 21/c        '
_cod_original_formula_sum        'C26 H22 N6 '
_cod_database_code               4029094