Highly Enantioselective Synthesis of 3,4-Dihydropyrans through a Phosphine-Catalyzed [4+2] Annulation of Allenones and β,γ-Unsaturated α-Keto Esters.
Yao, Weijun; Dou, Xiaowei; Lu, Yixin; Journal of the American Chemical Society 137 (2015) 54–57; doi:10.1021/ja5109358

data_4123091
_publ_section_title
;
 Highly Enantioselective Synthesis of 3,4-Dihydropyrans through a
 Phosphine-Catalyzed [4+2] Annulation of Allenones and \b,\g-Unsaturated
 \a-Keto Esters.
;
_journal_issue                   1
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              54
_journal_page_last               57
_journal_paper_doi               10.1021/ja5109358
_journal_volume                  137
_journal_year                    2015
_chemical_formula_sum            'C14 H20 O4'
_chemical_formula_weight         252.30
_space_group_crystal_system      orthorhombic
_space_group_IT_number           19
_space_group_name_Hall           'P 2ac 2ab'
_space_group_name_H-M_alt        'P 21 21 21'
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2013
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   6.8511(5)
_cell_length_b                   11.9553(9)
_cell_length_c                   16.4478(12)
_cell_measurement_reflns_used    9822
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      66.51
_cell_measurement_theta_min      2.69
_cell_volume                     1347.19(17)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-2013 (Sheldrick, 2013)'
_computing_structure_solution    'SHELXS-97 (Sheldrick 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker D8 Venture'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0496
_diffrn_reflns_av_unetI/netI     0.0192
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 1.000
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            24807
_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 1.000
_diffrn_reflns_theta_full        66.500
_diffrn_reflns_theta_max         66.509
_diffrn_reflns_theta_min         4.572
_exptl_absorpt_coefficient_mu    0.739
_exptl_absorpt_correction_T_max  0.7528
_exptl_absorpt_correction_T_min  0.5873
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            Colourless
_exptl_crystal_density_diffrn    1.244
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'Not Measured'
_exptl_crystal_description       Plate
_exptl_crystal_F_000             544
_exptl_crystal_size_max          0.42
_exptl_crystal_size_mid          0.30
_exptl_crystal_size_min          0.09
_refine_diff_density_max         0.419
_refine_diff_density_min         -0.548
_refine_diff_density_rms         0.240
_refine_ls_abs_structure_details
; 
 Flack x determined using 980 quotients [(I+)-(I-)]/[(I+)+(I-)] 
 (Parsons and Flack (2004), Acta Cryst. A60, s61). 
;
_refine_ls_abs_structure_Flack   0.02(4)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.126
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     167
_refine_ls_number_reflns         2385
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.126
_refine_ls_R_factor_all          0.0365
_refine_ls_R_factor_gt           0.0364
_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^)+(0.0553P)^2^+0.1943P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0894
_refine_ls_wR_factor_ref         0.0895
_reflns_Friedel_coverage         0.702
_reflns_Friedel_fraction_full    1.000
_reflns_Friedel_fraction_max     1.000
_reflns_number_gt                2376
_reflns_number_total             2385
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja5109358_si_003.cif
_cod_data_source_block           E073
_cod_depositor_comments
;
The following automatic conversions were performed:

'_exptl_absorpt_correction_type' value 'Multi-scan' changed to
'multi-scan' according to
/home/saulius/struct/COD-crude-data--automatic-downloads/rss-feeds/ACS/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 2935 2014-11-11 08:27:57Z andrius 

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'Not Measured' 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 

 Adding full bibliography for 4123091--4123092.cif.
;
_cod_database_code               4123091
_shelxl_version_number           2013-4
_shelx_res_checksum              7731
_shelx_hkl_checksum              96254