Lewis acid mediated reactions of 1-cyclopropyl-2-arylethanones with allenic esters: a facile synthetic protocol for the preparation of dihydrofuro[2,3-h]chromen-2-one derivatives.
Shi, Min; Tang, Xiang-Ying; Yang, Yong-Hua; Organic letters 9 (2007) 4017–4020; doi:10.1021/ol701713y

data_1505537
_publ_section_title
;
 Lewis acid mediated reactions of 1-cyclopropyl-2-arylethanones with
 allenic esters: a facile synthetic protocol for the preparation of
 dihydrofuro[2,3-h]chromen-2-one derivatives.
;
_journal_issue                   20
_journal_name_full               'Organic letters'
_journal_page_first              4017
_journal_page_last               4020
_journal_paper_doi               10.1021/ol701713y
_journal_volume                  9
_journal_year                    2007
_chemical_formula_sum            'C16 H16 O3'
_chemical_formula_weight         256.29
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   7.1088(10)
_cell_length_b                   8.1024(11)
_cell_length_c                   22.341(3)
_cell_measurement_reflns_used    1802
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      47.910
_cell_measurement_theta_min      6.014
_cell_volume                     1286.8(3)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SHELXTL'
_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      293(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  0.0840
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_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       28
_diffrn_reflns_limit_l_min       -25
_diffrn_reflns_number            7557
_diffrn_reflns_theta_full        27.00
_diffrn_reflns_theta_max         27.00
_diffrn_reflns_theta_min         1.82
_exptl_absorpt_coefficient_mu    0.091
_exptl_absorpt_correction_T_max  1.0000
_exptl_absorpt_correction_T_min  0.7807
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.323
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prismatic
_exptl_crystal_F_000             544
_exptl_crystal_size_max          0.412
_exptl_crystal_size_mid          0.301
_exptl_crystal_size_min          0.097
_refine_diff_density_max         0.156
_refine_diff_density_min         -0.142
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_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -10(10)
_refine_ls_extinction_coef       0.030(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   0.918
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_refine_ls_matrix_type           full
_refine_ls_number_parameters     175
_refine_ls_number_reflns         1649
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.918
_refine_ls_R_factor_all          0.0526
_refine_ls_R_factor_gt           0.0399
_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^)+(0.0434P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0852
_refine_ls_wR_factor_ref         0.0886
_reflns_number_gt                1223
_reflns_number_total             1649
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol701713y-file002.cif
_cod_data_source_block           cd27273
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' 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_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               1505537