Intramolecular O-H...O Hydrogen-Bond-Mediated Reversal in the Partitioning of Conformationally Restricted Triplet 1,4-Biradicals and Amplification of Diastereodifferentiation in Their Lifetimes
Jarugu Narasimha Moorthy; Subhas Samanta; Apurba L. Koner; Satyajit Saha; Werner M. Nau; Journal of the American Chemical Society 130 (2008) 13608–13617; doi:10.1021/ja8032179

data_4108454
_publ_contact_author_address
;Departmet of chemistry
Indian Institute of Technology - Kanpur
Kanpur - 208 016
INDIA
;
_publ_contact_author_email       moorthy@iitk.ac.in
_publ_contact_author_fax         +915122597436
_publ_contact_author_name        'Prof. J. N. Moorthy'
_publ_contact_author_phone       +915122597498
_publ_section_title
;
 Intramolecular O-H...O Hydrogen-Bond-Mediated Reversal in the
 Partitioning of Conformationally Restricted Triplet 1,4-Biradicals and
 Amplification of Diastereodifferentiation in Their Lifetimes
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              13608
_journal_page_last               13617
_journal_paper_doi               10.1021/ja8032179
_journal_volume                  130
_journal_year                    2008
_chemical_formula_moiety         'C19 H20 O3'
_chemical_formula_sum            'C19 H20 O3'
_chemical_formula_weight         296.35
_chemical_melting_point          335(1)
_chemical_name_common
'(2R,3R)-3-methyl-4-oxo-1,4-diphenylbutan-2-yl acetate'
_chemical_name_systematic
;
 (2R,3R)-3-methyl-4-oxo-1,4-diphenylbutan-2-yl acetate
;
_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                   9.3238(6)
_cell_length_b                   9.8521(6)
_cell_length_c                   17.4034(12)
_cell_measurement_temperature    293(2)
_cell_volume                     1598.66(18)
_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    'Bruker SHELXTL'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.992
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device_type  '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  0.0370
_diffrn_reflns_av_sigmaI/netI    0.0488
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       23
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            10593
_diffrn_reflns_theta_full        28.31
_diffrn_reflns_theta_max         28.31
_diffrn_reflns_theta_min         2.34
_exptl_absorpt_coefficient_mu    0.082
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.231
_exptl_crystal_density_meas      0
_exptl_crystal_description       clusters
_exptl_crystal_F_000             632
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.258
_refine_diff_density_min         -0.276
_refine_diff_density_rms         0.055
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   1.0(15)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.097
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     199
_refine_ls_number_reflns         3915
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.097
_refine_ls_R_factor_all          0.0717
_refine_ls_R_factor_gt           0.0527
_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^)+(0.0598P)^2^+0.4864P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1202
_refine_ls_wR_factor_ref         0.1437
_reflns_number_gt                3127
_reflns_number_total             3915
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja8032179_si_002.cif
_cod_data_source_block           9-anti
_cod_database_code               4108454