Hyperconjugation Involving Strained Carbon-Carbon Bonds. Structural Analysis of Ester and Ether Derivatives and One-Bond 13C-13C Coupling Constants of α- and β-Nopinol
Shinn Dee Yeoh; Colin E. Skene; Jonathan M. White; Journal of Organic Chemistry 78 (2013) 311–319; doi:10.1021/jo3020243

data_4027846
_publ_section_title
;
 Hyperconjugation Involving Strained Carbon-Carbon Bonds. Structural
 Analysis of Ester and Ether Derivatives and One-Bond 13C-13C Coupling
 Constants of \a- and \b-Nopinol
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              311
_journal_page_last               319
_journal_paper_doi               10.1021/jo3020243
_journal_volume                  78
_journal_year                    2013
_chemical_absolute_configuration rmad
_chemical_formula_sum            'C20 H22 O2'
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_space_group_IT_number           5
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'C 2y'
_symmetry_space_group_name_H-M   'C 1 2 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                 96.453(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   18.5270(3)
_cell_length_b                   7.48900(10)
_cell_length_c                   11.4673(2)
_cell_measurement_reflns_used    4303
_cell_measurement_temperature    130(2)
_cell_measurement_theta_max      73.2407
_cell_measurement_theta_min      5.8275
_cell_volume                     1580.99(4)
_computing_cell_refinement
;
CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.33.55 (release 05-01-2010 CrysAlis171 .NET)
(compiled Jan  5 2010,16:28:46)
;
_computing_data_collection
;
CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.33.55 (release 05-01-2010 CrysAlis171 .NET)
(compiled Jan  5 2010,16:28:46)
;
_computing_data_reduction
;
CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.33.55 (release 05-01-2010 CrysAlis171 .NET)
(compiled Jan  5 2010,16:28:46)
;
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      130(2)
_diffrn_measured_fraction_theta_full 0.971
_diffrn_measured_fraction_theta_max 0.971
_diffrn_measurement_device_type  'Xcalibur, Sapphire3'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Enhance (Cu) x-ray Source'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0219
_diffrn_reflns_av_sigmaI/netI    0.0208
_diffrn_reflns_limit_h_max       22
_diffrn_reflns_limit_h_min       -22
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            4698
_diffrn_reflns_theta_full        73.40
_diffrn_reflns_theta_max         73.40
_diffrn_reflns_theta_min         5.83
_exptl_absorpt_coefficient_mu    0.612
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.95926
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.33.55 (release 05-01-2010 CrysAlis171 .NET)
(compiled Jan  5 2010,16:28:46)
empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.237
_exptl_crystal_description       slab
_exptl_crystal_F_000             632
_exptl_crystal_size_max          0.3696
_exptl_crystal_size_mid          0.2800
_exptl_crystal_size_min          0.0720
_refine_diff_density_max         0.229
_refine_diff_density_min         -0.142
_refine_diff_density_rms         0.036
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.1(2)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.050
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     199
_refine_ls_number_reflns         2212
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.050
_refine_ls_R_factor_all          0.0364
_refine_ls_R_factor_gt           0.0351
_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^)+(0.0728P)^2^+0.2526P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0974
_refine_ls_wR_factor_ref         0.0986
_reflns_number_gt                2142
_reflns_number_total             2212
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo3020243_si_008.cif
_cod_data_source_block           jmwsdy70
_cod_database_code               4027846