Ring-Opening Polymerization of Lactides Catalyzed by Natural Amino-Acid Based Zinc Catalysts
Donald J. Darensbourg; Osit Karroonnirun; Inorganic Chemistry 49 (2010) 2360–2371; doi:10.1021/ic902271x

data_4315038
_publ_section_title
;
 Ring-Opening Polymerization of Lactides Catalyzed by Natural Amino-Acid
 Based Zinc Catalysts
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              2360
_journal_page_last               2371
_journal_paper_doi               10.1021/ic902271x
_journal_volume                  49
_journal_year                    2010
_chemical_absolute_configuration rm
_chemical_formula_sum            'C32 H55 N3 O Si2 Zn'
_chemical_formula_weight         619.34
_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                   8.719(4)
_cell_length_b                   16.535(8)
_cell_length_c                   24.901(12)
_cell_measurement_temperature    150(2)
_cell_volume                     3590(3)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'X-SEED (Barbour, 2001)'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      150(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_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  0.1231
_diffrn_reflns_av_sigmaI/netI    0.0920
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       20
_diffrn_reflns_limit_k_min       -20
_diffrn_reflns_limit_l_max       30
_diffrn_reflns_limit_l_min       -30
_diffrn_reflns_number            32055
_diffrn_reflns_theta_full        25.99
_diffrn_reflns_theta_max         25.99
_diffrn_reflns_theta_min         2.05
_exptl_absorpt_coefficient_mu    0.777
_exptl_absorpt_correction_T_max  0.8728
_exptl_absorpt_correction_T_min  0.8601
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS; (Sheldrick, 2006)'
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.146
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1336
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.18
_refine_diff_density_max         0.620
_refine_diff_density_min         -0.538
_refine_diff_density_rms         0.082
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.012(15)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.014
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     373
_refine_ls_number_reflns         7063
_refine_ls_number_restraints     4
_refine_ls_restrained_S_all      1.014
_refine_ls_R_factor_all          0.0779
_refine_ls_R_factor_gt           0.0539
_refine_ls_shift/su_max          0.149
_refine_ls_shift/su_mean         0.006
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0664P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1190
_refine_ls_wR_factor_ref         0.1299
_reflns_number_gt                5481
_reflns_number_total             7063
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic902271x_si_001_1.cif
_cod_data_source_block           andr
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' according to the built-in table from CIF Core
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1646 2011-03-28 12:23:43Z adriana 
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_cod_database_code               4315038