Stereoconvergent [1,2]- and [1,4]-Wittig Rearrangements of 2-Silyl-6-aryl-5,6-dihydropyrans: A Tale of Steric vs Electronic Regiocontrol of Divergent Pathways.
Mori-Quiroz, Luis M; Maleczka, Jr, Robert E; The Journal of organic chemistry 80 (2015) 1163–; doi:10.1021/jo5026942

data_4030546
_publ_section_title
;
 Stereoconvergent [1,2]- and [1,4]-Wittig Rearrangements of
 2-Silyl-6-aryl-5,6-dihydropyrans: A Tale of Steric vs Electronic
 Regiocontrol of Divergent Pathways.
;
_journal_issue                   2
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              1163
_journal_paper_doi               10.1021/jo5026942
_journal_volume                  80
_journal_year                    2015
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C21 H24 N2 O6 Si'
_chemical_formula_sum            'C21 H24 N2 O6 Si'
_chemical_formula_weight         428.51
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_Int_Tables_number      19
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   6.6788(4)
_cell_length_b                   9.7813(6)
_cell_length_c                   33.0675(16)
_cell_measurement_reflns_used    2727
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      65.88
_cell_measurement_theta_min      5.25
_cell_volume                     2160.2(2)
_computing_cell_refinement       'APEX2 (BRUKER, V2010.11-3, 2010)'
_computing_data_collection       'COSMO (BRUKER, V1.61, 2009)'
_computing_data_reduction        'SAINT (BRUKER, V7.68A, 2010)'
_computing_molecular_graphics
'SHELXTL (Sheldrick, Acta Cryst. A64 2008, 112-122)'
_computing_publication_material
'SHELXTL (Sheldrick, Acta Cryst. A64 2008, 112-122)'
_computing_structure_refinement
'SHELXL (Sheldrick, Acta Cryst. A64 2008, 112-122)'
_computing_structure_solution
'SHELXS (Sheldrick, Acta Cryst. A64 2008, 112-122)'
_diffrn_ambient_temperature      173(2)
_diffrn_detector_area_resol_mean 836.6
_diffrn_measured_fraction_theta_full 0.971
_diffrn_measured_fraction_theta_max 0.971
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\w,and/f 0.5 deg'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0596
_diffrn_reflns_av_sigmaI/netI    0.0743
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       38
_diffrn_reflns_limit_l_min       -36
_diffrn_reflns_number            8614
_diffrn_reflns_theta_full        67.26
_diffrn_reflns_theta_max         67.26
_diffrn_reflns_theta_min         2.67
_diffrn_source                   'fine-focus sealed tube'
_exptl_absorpt_coefficient_mu    1.304
_exptl_absorpt_correction_T_max  0.9644
_exptl_absorpt_correction_T_min  0.6531
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.318
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             904
_exptl_crystal_size_max          0.36
_exptl_crystal_size_mid          0.09
_exptl_crystal_size_min          0.03
_refine_diff_density_max         0.835
_refine_diff_density_min         -0.324
_refine_diff_density_rms         0.087
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.03(9)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.088
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     274
_refine_ls_number_reflns         3585
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.088
_refine_ls_R_factor_all          0.1006
_refine_ls_R_factor_gt           0.0834
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1223P)^2^+2.3890P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2177
_refine_ls_wR_factor_ref         0.2276
_reflns_number_gt                2892
_reflns_number_total             3585
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo5026942_si_003.cif
_cod_data_source_block           rem312
_cod_depositor_comments
;
The following automatic conversions were performed:

'_exptl_absorpt_correction_type' value 'Multi-scan' changed to
'multi-scan' 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 3008 2015-01-20 13:52:24Z robertas 
;
_cod_database_code               4030546
_contact_crystallographer_name   'Richard Staples'
_contact_crystallographer_email  staples@chemistry.msu.com