Tungsten-Promoted Diels−Alder Cycloaddition of Pyridines: Dearomatization of 2,6-Dimethoxypyridine Generates a Potent 2-Azadiene Synthon
Kosturko, George W.; Graham, Peter M.; Myers, William H.; Smith, Timothy M.; Sabat, Michal; Harman, W. Dean; Organometallics 27 (2008) 4513–; doi:10.1021/om800430p

data_4071857
_publ_section_title
;
 Tungsten-Promoted Diels&#x2212;Alder Cycloaddition of Pyridines:
 Dearomatization of 2,6-Dimethoxypyridine Generates a Potent 2-Azadiene
 Synthon
;
_journal_issue                   17
_journal_name_full               Organometallics
_journal_page_first              4513
_journal_paper_doi               10.1021/om800430p
_journal_volume                  27
_journal_year                    2008
_chemical_formula_sum            'C26 H39 B N9 O4 P W'
_chemical_formula_weight         767.29
_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   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 98.111(4)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   11.045(1)
_cell_length_b                   13.584(1)
_cell_length_c                   20.498(3)
_cell_measurement_reflns_used    3963
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      31.527
_cell_measurement_theta_min      3.645
_cell_volume                     3044.7(6)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.924
_diffrn_measured_fraction_theta_max 0.924
_diffrn_measurement_device_type  'Bruker SMART APEX CCD area detector'
_diffrn_measurement_method       'phi and omega 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  0.0400
_diffrn_reflns_av_sigmaI/netI    0.0442
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       25
_diffrn_reflns_limit_l_min       -25
_diffrn_reflns_number            27750
_diffrn_reflns_theta_full        32.265
_diffrn_reflns_theta_max         32.265
_diffrn_reflns_theta_min         3.422
_exptl_absorpt_coefficient_mu    3.890
_exptl_absorpt_correction_T_max  0.811820
_exptl_absorpt_correction_T_min  0.626739
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'Bruker SADABS'
_exptl_crystal_colour            orange
_exptl_crystal_density_diffrn    1.674
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             1488
_exptl_crystal_size_max          0.19
_exptl_crystal_size_mid          0.07
_exptl_crystal_size_min          0.06
_refine_diff_density_max         2.521
_refine_diff_density_min         -2.281
_refine_diff_density_rms         0.206
_refine_ls_extinction_coef       none
_refine_ls_extinction_method     none
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_refine_ls_number_reflns         5303
_refine_ls_number_restraints     0
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_refine_ls_R_factor_all          0.0671
_refine_ls_R_factor_gt           0.0567
_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^)+(0.1474P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1793
_refine_ls_wR_factor_ref         0.1879
_reflns_number_gt                4492
_reflns_number_total             5303
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            om800430p_si_002.cif
_cod_data_source_block           C26H39BN9O4PW
_cod_depositor_comments
;
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 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not measured' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
;
_cod_original_cell_volume        3044.7(4)
_cod_original_sg_symbol_H-M      P2(1)/c
_cod_database_code               4071857