Direct Construction of Quaternary Carbons from Tertiary Alcohols via Photoredox-Catalyzed Fragmentation of tert-Alkyl N-Phthalimidoyl Oxalates
Gregory L. Lackner; Kyle W. Quasdorf; Larry E. Overman; Journal of the American Chemical Society 135 (2013) 15342–15345; doi:10.1021/ja408971t

data_4120977
_publ_section_title
;
 Direct Construction of Quaternary Carbons from Tertiary Alcohols via
 Photoredox-Catalyzed Fragmentation of tert-Alkyl N-Phthalimidoyl Oxalates
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              15342
_journal_page_last               15345
_journal_paper_doi               10.1021/ja408971t
_journal_volume                  135
_journal_year                    2013
_chemical_absolute_configuration syn
_chemical_formula_sum            'C25 H44 O3'
_chemical_formula_weight         392.60
_space_group_crystal_system      monoclinic
_space_group_IT_number           4
_space_group_name_Hall           'P 2yb'
_space_group_name_H-M_alt        'P 1 21 1'
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-2013
_cell_angle_alpha                90
_cell_angle_beta                 105.3106(9)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   13.9764(11)
_cell_length_b                   6.0441(5)
_cell_length_c                   14.2367(11)
_cell_measurement_reflns_used    5436
_cell_measurement_temperature    143(2)
_cell_measurement_theta_max      28.06
_cell_measurement_theta_min      2.38
_cell_volume                     1159.96(16)
_computing_cell_refinement       'Bruker SAINT 7.68a, 2009'
_computing_data_collection       'Bruker APEX2 2011.4-1, 2011'
_computing_data_reduction        'Bruker SAINT 7.68a, 2009'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-2013 (Sheldrick, 2013)'
_computing_structure_solution    'Bruker SHELXTL 2008/4'
_diffrn_ambient_temperature      143(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.956
_diffrn_measurement_device_type  'Bruker SMART APEX II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0270
_diffrn_reflns_av_unetI/netI     0.0376
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.956
_diffrn_reflns_limit_h_max       18
_diffrn_reflns_limit_h_min       -18
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            13330
_diffrn_reflns_point_group_measured_fraction_full 0.998
_diffrn_reflns_point_group_measured_fraction_max 0.929
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         28.246
_diffrn_reflns_theta_min         1.483
_diffrn_source                   'fine-focus sealed tube'
_exptl_absorpt_coefficient_mu    0.071
_exptl_absorpt_correction_T_max  0.8621
_exptl_absorpt_correction_T_min  0.7824
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Bruker SADABS 2008/1'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.124
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    not_measured
_exptl_crystal_description       irregular
_exptl_crystal_F_000             436
_exptl_crystal_size_max          0.197
_exptl_crystal_size_mid          0.159
_exptl_crystal_size_min          0.144
_refine_diff_density_max         0.249
_refine_diff_density_min         -0.148
_refine_diff_density_rms         0.036
_refine_ls_abs_structure_details
; 
 Flack x determined using 1836 quotients [(I+)-(I-)]/[(I+)+(I-)] 
 (Parsons and Flack (2004), Acta Cryst. A60, s61). 
;
_refine_ls_abs_structure_Flack   0.1(5)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.026
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     261
_refine_ls_number_reflns         5314
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.026
_refine_ls_R_factor_all          0.0505
_refine_ls_R_factor_gt           0.0402
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0570P)^2^+0.0576P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0949
_refine_ls_wR_factor_ref         0.1005
_reflns_Friedel_coverage         0.777
_reflns_Friedel_fraction_full    0.996
_reflns_Friedel_fraction_max     0.896
_reflns_number_gt                4612
_reflns_number_total             5314
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja408971t_si_003.cif
_cod_data_source_block           leo265
_cod_depositor_comments
;
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_database_code               4120977
_shelx_estimated_absorpt_t_min   0.986
_shelx_estimated_absorpt_t_max   0.990
_shelxl_version_number           2013-3
_shelx_res_checksum              251