Highly facile and stereoselective intramolecular [2+2]photocycloadditions of bis(alkenoyl)ketenedithioacetals
Joseph, Bubbly K.; Verghese, Babu; Sudarsanakumar, C.; Deepa, S.; Viswam, Dhanya; Chandran, Prakash; Asokan, C. V.; Chemical Communications  (2002) 736–; doi:10.1039/b200395n

data_7114118
_publ_section_title
;
 Highly facile and stereoselective intramolecular [2+2]photocycloadditions
 of bis(alkenoyl)ketenedithioacetals
;
_journal_issue                   7
_journal_name_full               'Chemical Communications'
_journal_page_first              736
_journal_paper_doi               10.1039/b200395n
_journal_year                    2002
_chemical_formula_sum            'C22 H18 O2 S2'
_chemical_formula_weight         378.48
_chemical_name_systematic
; 
? 
;
_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                 106.50
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.998(4)
_cell_length_b                   16.579(6)
_cell_length_c                   13.372(6)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      35
_cell_measurement_theta_min      25
_cell_volume                     1912.7(14)
_computing_cell_refinement       CAD4-Programs
_computing_data_collection       CAD4-Programs
_computing_data_reduction        Molen
_computing_molecular_graphics    ORTEP
_computing_publication_material  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.964
_diffrn_measured_fraction_theta_max 0.964
_diffrn_measurement_device_type  CAD4-Diffractometer
_diffrn_measurement_method       'Omega-TwoTheta Scan'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54180
_diffrn_reflns_av_R_equivalents  0.0000
_diffrn_reflns_av_sigmaI/netI    0.0227
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       20
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            3608
_diffrn_reflns_theta_full        69.88
_diffrn_reflns_theta_max         69.88
_diffrn_reflns_theta_min         4.36
_diffrn_standards_interval_time  '1 Hour'
_diffrn_standards_number         2
_exptl_absorpt_coefficient_mu    2.622
_exptl_crystal_colour            Yellow
_exptl_crystal_density_diffrn    1.314
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Prismatic
_exptl_crystal_F_000             792
_exptl_crystal_size_max          0.18
_exptl_crystal_size_mid          0.13
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.430
_refine_diff_density_min         -0.278
_refine_diff_density_rms         0.047
_refine_ls_extinction_coef       0.0010(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.050
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     236
_refine_ls_number_reflns         3608
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.050
_refine_ls_R_factor_all          0.0562
_refine_ls_R_factor_gt           0.0507
_refine_ls_shift/su_max          0.003
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0755P)^2^+1.0429P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1391
_refine_ls_wR_factor_ref         0.1455
_reflns_number_gt                3267
_reflns_number_total             3608
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b200395n.txt
_cod_data_source_block           compound_2a
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to
/usr/data/users/saulius/automatic-downloads/retrospective/RSC/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 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc
w=1/[\s^2^(Fo^2^)+(0.0755P)^2^+1.0429P] where P=(Fo^2^+2Fc^2^)/3' was
changed to 'calc'. New tag '_refine_ls_weighting_details' was
created. The value of the new tag was set to
'w=1/[\s^2^(Fo^2^)+(0.0755P)^2^+1.0429P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_sg_symbol_H-M      P21/c
_cod_database_code               7114118