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_4071859
_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            'C25 H39 B N8 O5.5 P W'
_chemical_formula_weight         765.27
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 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                 94.58(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   20.548(4)
_cell_length_b                   13.322(3)
_cell_length_c                   22.697(5)
_cell_measurement_reflns_used    7842
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      30.622
_cell_measurement_theta_min      2.863
_cell_volume                     6193(2)
_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 0.991
_diffrn_measured_fraction_theta_max 0.991
_diffrn_measurement_device_type  'Bruker SMART APEX CCD detector'
_diffrn_measurement_method       'omega and phi 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  0.0292
_diffrn_reflns_av_sigmaI/netI    0.0449
_diffrn_reflns_limit_h_max       33
_diffrn_reflns_limit_h_min       -33
_diffrn_reflns_limit_k_max       21
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       36
_diffrn_reflns_limit_l_min       -36
_diffrn_reflns_number            49104
_diffrn_reflns_theta_full        34.99
_diffrn_reflns_theta_max         34.99
_diffrn_reflns_theta_min         1.99
_exptl_absorpt_coefficient_mu    3.832
_exptl_absorpt_correction_T_max  0.80603
_exptl_absorpt_correction_T_min  0.49762
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'Bruker SADABS'
_exptl_crystal_colour            orange
_exptl_crystal_density_diffrn    1.641
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             3064
_exptl_crystal_size_max          0.33
_exptl_crystal_size_mid          0.13
_exptl_crystal_size_min          0.11
_refine_diff_density_max         3.006
_refine_diff_density_min         -2.583
_refine_diff_density_rms         0.174
_refine_ls_extinction_coef       0.00002(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.027
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     771
_refine_ls_number_reflns         27035
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.027
_refine_ls_R_factor_all          0.0641
_refine_ls_R_factor_gt           0.0401
_refine_ls_shift/su_max          0.003
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0703P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1058
_refine_ls_wR_factor_ref         0.1158
_reflns_number_gt                19761
_reflns_number_total             27035
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            om800430p_si_004.cif
_cod_data_source_block           C25H39BN8O5PW
_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_sg_symbol_H-M      P2(1)/n
_cod_original_formula_sum        'C25 H39 B N8 O5.50 P W'
_cod_database_code               4071859