Observation of neighboring ortho-hydroxyl group participation in organocatalytic asymmetric sequential Michael-lactonization reactions: synthesis of highly substituted chiral spirodihydrocoumarins.
Ramachary, Dhevalapally B.; Madhavachary, R.; Prasad, M. Shiva; Organic & biomolecular chemistry 10 (2012) 5825–5829; doi:10.1039/c2ob07122c

data_7152447
_publ_section_title
;
 Observation of neighboring ortho-hydroxyl group participation in
 organocatalytic asymmetric sequential Michael-lactonization reactions:
 synthesis of highly substituted chiral spirodihydrocoumarins.
;
_journal_issue                   30
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              5825
_journal_page_last               5829
_journal_paper_doi               10.1039/c2ob07122c
_journal_volume                  10
_journal_year                    2012
_chemical_absolute_configuration ad
_chemical_formula_sum            'C14 H13 N O5'
_chemical_formula_weight         275.28
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_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                   6.0553(2)
_cell_length_b                   13.8095(5)
_cell_length_c                   15.5347(5)
_cell_measurement_reflns_used    1861
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      71.6185
_cell_measurement_theta_min      2.8421
_cell_volume                     1299.02(8)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_detector_area_resol_mean 16.3291
_diffrn_measured_fraction_theta_full 0.987
_diffrn_measured_fraction_theta_max 0.987
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0146
_diffrn_reflns_av_sigmaI/netI    0.0285
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -4
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            3960
_diffrn_reflns_theta_full        71.76
_diffrn_reflns_theta_max         71.76
_diffrn_reflns_theta_min         4.28
_exptl_absorpt_coefficient_mu    0.912
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.95505
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.418
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       black
_exptl_crystal_F_000             576.0
_exptl_crystal_size_max          0.36
_exptl_crystal_size_mid          0.24
_exptl_crystal_size_min          0.16
_refine_diff_density_max         0.129
_refine_diff_density_min         -0.165
_refine_diff_density_rms         0.031
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.3(3)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.075
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     181
_refine_ls_number_reflns         2486
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.075
_refine_ls_R_factor_all          0.0539
_refine_ls_R_factor_gt           0.0438
_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^)+(0.0536P)^2^+0.1134P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1094
_refine_ls_wR_factor_ref         0.1146
_reflns_number_gt                2093
_reflns_number_total             2486
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c2ob07122c.txt
_cod_data_source_block           dbr22
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' 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 1891 2012-01-12 08:04:46Z andrius 
;
_cod_original_sg_symbol_H-M      'P2(1)2(1)2(1) '
_cod_database_code               7152447