Diastereoselective Synthesis of Substituted Tetrahydrofurans via Prins Cyclization of Enol Ethers.
Gogoi, Paramartha; Das, Vijay K.; Saikia, Anil K.; The Journal of organic chemistry 79 (2014) 8592–8598; doi:10.1021/jo501197y

data_4029929
_publ_section_title
;
 Diastereoselective Synthesis of Substituted Tetrahydrofurans via Prins
 Cyclization of Enol Ethers.
;
_journal_issue                   18
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              8592
_journal_page_last               8598
_journal_paper_doi               10.1021/jo501197y
_journal_volume                  79
_journal_year                    2014
_chemical_formula_sum            'C21 H21 Br O4'
_chemical_formula_weight         417.29
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_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 101.335(9)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   16.043(2)
_cell_length_b                   5.0891(7)
_cell_length_c                   24.389(3)
_cell_measurement_temperature    293(2)
_cell_volume                     1952.4(4)
_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    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.962
_diffrn_measured_fraction_theta_max 0.962
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_monochromator  graphite
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_diffrn_radiation_type           MoK\a
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_diffrn_reflns_limit_h_max       18
_diffrn_reflns_limit_h_min       -18
_diffrn_reflns_limit_k_max       5
_diffrn_reflns_limit_k_min       -5
_diffrn_reflns_limit_l_max       28
_diffrn_reflns_limit_l_min       -27
_diffrn_reflns_number            13760
_diffrn_reflns_theta_full        24.49
_diffrn_reflns_theta_max         24.49
_diffrn_reflns_theta_min         1.29
_exptl_absorpt_coefficient_mu    2.128
_exptl_absorpt_correction_T_max  0.608
_exptl_absorpt_correction_T_min  0.486
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Face indexing'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.420
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             856
_exptl_crystal_size_max          0.34
_exptl_crystal_size_mid          0.28
_exptl_crystal_size_min          0.23
_refine_diff_density_max         0.768
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_refine_ls_extinction_method     none
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_refine_ls_hydrogen_treatment    mixed
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_refine_ls_number_parameters     236
_refine_ls_number_reflns         3108
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_refine_ls_R_factor_all          0.2206
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_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^)+(0.0300P)^2^+4.5000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1835
_refine_ls_wR_factor_ref         0.2315
_reflns_number_gt                1168
_reflns_number_total             3108
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo501197y_si_001.cif
_cod_data_source_block           para3
_cod_depositor_comments
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The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to
/home/saulius/struct/COD-crude-data--automatic-downloads/rss-feeds/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 2281 2013-09-26 08:29:07Z andrius 

 Adding full bibliography for 4029929.cif.
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_cod_original_sg_symbol_H-M      P21/c
_cod_database_code               4029929