Tandem Michael addition/cyclization reaction of 2,3-allenoates with organozincs: facile synthesis of isocoumarins.
Chen, Bo; Ma, Shengming; Organic letters 15 (2013) 3884–3887; doi:10.1021/ol401625t

data_1512198
_publ_section_title
;
 Tandem Michael addition/cyclization reaction of 2,3-allenoates with
 organozincs: facile synthesis of isocoumarins.
;
_journal_issue                   15
_journal_name_full               'Organic letters'
_journal_page_first              3884
_journal_page_last               3887
_journal_paper_doi               10.1021/ol401625t
_journal_volume                  15
_journal_year                    2013
_chemical_formula_sum            'C20 H18 O3'
_chemical_formula_weight         306.34
_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                 110.152(5)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   13.1393(16)
_cell_length_b                   9.7705(12)
_cell_length_c                   27.212(3)
_cell_measurement_temperature    296(2)
_cell_volume                     3279.5(7)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_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    0.0242
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       31
_diffrn_reflns_limit_l_min       -32
_diffrn_reflns_number            37301
_diffrn_reflns_theta_full        25.01
_diffrn_reflns_theta_max         25.01
_diffrn_reflns_theta_min         1.65
_exptl_absorpt_coefficient_mu    0.083
_exptl_absorpt_correction_T_max  0.9821
_exptl_absorpt_correction_T_min  0.9709
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.241
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1296
_exptl_crystal_size_max          0.36
_exptl_crystal_size_mid          0.32
_exptl_crystal_size_min          0.22
_refine_diff_density_max         0.163
_refine_diff_density_min         -0.154
_refine_diff_density_rms         0.032
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.025
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     421
_refine_ls_number_reflns         5790
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.025
_refine_ls_R_factor_all          0.0638
_refine_ls_R_factor_gt           0.0410
_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^)+(0.0538P)^2^+0.7828P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1045
_refine_ls_wR_factor_ref         0.1216
_reflns_number_gt                4152
_reflns_number_total             5790
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol401625t_si_002.cif
_cod_data_source_block           z
_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 
;
_cod_original_sg_symbol_H-M      P2(1)/c
_cod_database_code               1512198