Base catalysed synthesis of thiochromans and azo-linked chromenes using allenylphosphonates.
Phani Pavan, M.; Nagarjuna Reddy, M.; Bhuvan Kumar, N. N.; Kumara Swamy, K. C.; Organic & biomolecular chemistry 10 (2012) 8113–8118; doi:10.1039/c2ob26285a

data_7152669
_publ_section_title
;
 Base catalysed synthesis of thiochromans and azo-linked chromenes using
 allenylphosphonates.
;
_journal_issue                   40
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              8113
_journal_page_last               8118
_journal_paper_doi               10.1039/c2ob26285a
_journal_volume                  10
_journal_year                    2012
_chemical_formula_sum            'C21 H23 O4 P S'
_chemical_formula_weight         402.43
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_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                 111.543(9)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   10.667(2)
_cell_length_b                   9.913(2)
_cell_length_c                   20.138(4)
_cell_measurement_reflns_used    6436
_cell_measurement_temperature    298(2)
_cell_measurement_theta_max      26.04
_cell_measurement_theta_min      2.32
_cell_volume                     1980.7(7)
_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      298(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_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  0.0352
_diffrn_reflns_av_sigmaI/netI    0.0252
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       23
_diffrn_reflns_limit_l_min       -23
_diffrn_reflns_number            18427
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         2.05
_exptl_absorpt_coefficient_mu    0.268
_exptl_absorpt_correction_T_max  0.9434
_exptl_absorpt_correction_T_min  0.8866
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'SADABS, SHELDRICK (1996)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.350
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       blocks
_exptl_crystal_F_000             848
_exptl_crystal_size_max          0.46
_exptl_crystal_size_mid          0.38
_exptl_crystal_size_min          0.22
_refine_diff_density_max         0.481
_refine_diff_density_min         -0.266
_refine_diff_density_rms         0.051
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.301
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     246
_refine_ls_number_reflns         3484
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.301
_refine_ls_R_factor_all          0.0728
_refine_ls_R_factor_gt           0.0697
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0302P)^2^+2.4646P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1355
_refine_ls_wR_factor_ref         0.1371
_reflns_number_gt                3357
_reflns_number_total             3484
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c2ob26285a.txt
_cod_data_source_block           kck(E)-8
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 1891 2012-01-12 08:04:46Z andrius 

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'none' was changed to '?' - the
value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
;
_cod_original_sg_symbol_H-M      P21/c
_cod_database_code               7152669