A tandem Prins spirocyclization for the stereoselective synthesis of tetrahydrospiro[chroman-2,4'-pyran] derivatives.
Subba Reddy, B. V.; Hanuman Reddy, V.; Medaboina, Durgaprasad; Sridhar, B.; Rami Reddy, Y. V.; Organic & biomolecular chemistry 14 (2016) 3234–3237; doi:10.1039/c5ob02639c

data_7154972
_publ_section_title
;
 A tandem Prins spirocyclization for the stereoselective synthesis of
 tetrahydrospiro[chroman-2,4'-pyran] derivatives.
;
_journal_issue                   12
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              3234
_journal_page_last               3237
_journal_paper_doi               10.1039/c5ob02639c
_journal_volume                  14
_journal_year                    2016
_chemical_formula_moiety         'C23 H22 O2'
_chemical_formula_sum            'C23 H22 O2'
_chemical_formula_weight         330.40
_space_group_crystal_system      monoclinic
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_space_group_name_Hall           '-C 2yc'
_space_group_name_H-M_alt        'C 1 2/c 1'
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/c 1'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2014/7
_audit_update_record
;
2015-12-03 deposited with the CCDC.
2016-02-10 downloaded from the CCDC.
;
_cell_angle_alpha                90
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_cell_measurement_temperature    294(2)
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_cell_volume                     3520.5(4)
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_computing_structure_solution    'SHELXL-2014/7 (Sheldrick, 2015)'
_diffrn_ambient_temperature      294(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.978
_diffrn_measurement_device_type  'Bruker SMART APEX CCD area-detector'
_diffrn_measurement_method       \w
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_refine_ls_extinction_method     none
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_refine_ls_number_restraints     0
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_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0688P)^2^+0.8190P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1251
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_reflns_number_gt                3396
_reflns_number_total             4266
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c5ob02639c2.cif
_cod_data_source_block           BB25m
_cod_depositor_comments          'Adding full bibliography for 7154972.cif.'
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_shelx_shelxl_version_number     2014/7
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