Reaction of Dimethoxycarbene-DMAD Zwitterion with 1,2-Diones and Anhydrides: A Novel Synthesis of Highly Substituted Dihydrofurans and Spirodihydrofurans
Vijay Nair; Ani Deepthi; Manojkumar Poonoth; Bindu Santhamma; Sreekumar Vellalath; Beneesh Pattoorpady Babu; Resmi Mohan; Eringathodi Suresh; Journal of Organic Chemistry 71 (2006) 2313–2319; doi:10.1021/jo052429k

data_4021552
_publ_section_title
;
 Reaction of Dimethoxycarbene-DMAD Zwitterion with 1,2-Diones
 and Anhydrides: A Novel Synthesis of Highly Substituted
 Dihydrofurans and Spirodihydrofurans
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              2313
_journal_page_last               2319
_journal_paper_doi               10.1021/jo052429k
_journal_volume                  71
_journal_year                    2006
_chemical_formula_sum            'C23 H22 O8'
_chemical_formula_weight         426.41
_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                 103.889(7)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.390(3)
_cell_length_b                   18.948(7)
_cell_length_c                   13.886(5)
_cell_measurement_temperature    296(2)
_cell_volume                     2143.0(14)
_computing_cell_refinement       'BRUKER SMART '
_computing_data_collection       'BRUKER SMART'
_computing_data_reduction        'BRUKER SAINT '
_computing_publication_material  ORTEP
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.965
_diffrn_measured_fraction_theta_max 0.965
_diffrn_measurement_device_type  'BRUKER SMART APEX CCD DIFFRACTOMETER'
_diffrn_measurement_method       'OMEGA-PHI SCAN'
_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  0.0244
_diffrn_reflns_av_sigmaI/netI    0.0287
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       22
_diffrn_reflns_limit_k_min       -22
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            10500
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         1.85
_exptl_absorpt_coefficient_mu    0.100
_exptl_crystal_colour            COLOURLESS
_exptl_crystal_density_diffrn    1.322
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       BLOCKS
_exptl_crystal_F_000             896
_exptl_crystal_size_max          0.34
_exptl_crystal_size_mid          0.26
_exptl_crystal_size_min          0.22
_refine_diff_density_max         0.198
_refine_diff_density_min         -0.225
_refine_diff_density_rms         0.045
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.124
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     284
_refine_ls_number_reflns         3755
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.124
_refine_ls_R_factor_all          0.0640
_refine_ls_R_factor_gt           0.0549
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0611P)^2^+0.7398P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1313
_refine_ls_wR_factor_ref         0.1363
_reflns_number_gt                3214
_reflns_number_total             3755
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo052429ksi20051206_123547.cif
_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 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc
w=1/[\s^2^(Fo^2^)+(0.0611P)^2^+0.7398P] 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^)+(0.0611P)^2^+0.7398P] 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      'P 21/c'
_cod_database_code               4021552