DABCO catalyzed domino Michael/hydroalkoxylation reaction involving α-alkynyl-β-aryl nitroolefins: excellent stereoselective access to dihydropyrano[3,2-c]chromenes, pyranonaphthoquinones and related heterocycles.
Biswas, Soumen; Dagar, Anuradha; Mobin, Shaikh M.; Samanta, Sampak; Organic & biomolecular chemistry 14 (2016) 1940–1945; doi:10.1039/c5ob02400e

data_7154877
_publ_section_title
;
 DABCO catalyzed domino Michael/hydroalkoxylation reaction involving
 \a-alkynyl-\b-aryl nitroolefins: excellent stereoselective access to
 dihydropyrano[3,2-c]chromenes, pyranonaphthoquinones and related
 heterocycles.
;
_journal_issue                   6
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              1940
_journal_page_last               1945
_journal_paper_doi               10.1039/c5ob02400e
_journal_volume                  14
_journal_year                    2016
_chemical_formula_sum            'C25 H20 O3'
_chemical_formula_weight         368.41
_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
_audit_update_record
;
2015-11-19 deposited with the CCDC.
2016-01-07 downloaded from the CCDC.
;
_cell_angle_alpha                90.00
_cell_angle_beta                 115.322(12)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   9.2495(10)
_cell_length_b                   8.8594(7)
_cell_length_c                   26.022(3)
_cell_measurement_reflns_used    4057
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      28.4920
_cell_measurement_theta_min      3.3520
_cell_volume                     1927.5(4)
_computing_cell_refinement       'CrysAlis RED, Oxford Diffraction Ltd.,'
_computing_data_collection       'CrysAlis CCD, Oxford Diffraction Ltd.,'
_computing_data_reduction        'CrysAlis RED, Oxford Diffraction Ltd.,'
_computing_molecular_graphics    Ortep3
_computing_publication_material  Shelx97
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_detector_area_resol_mean 15.9948
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'OXFORD DIFFRACTION SUPER NOVA'
_diffrn_measurement_method       \w/q-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  0.0903
_diffrn_reflns_av_sigmaI/netI    0.0467
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       30
_diffrn_reflns_limit_l_min       -30
_diffrn_reflns_number            17000
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         3.19
_exptl_absorpt_coefficient_mu    0.082
_exptl_absorpt_correction_T_max  0.9757
_exptl_absorpt_correction_T_min  0.9678
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlis RED, Oxford Diffraction Ltd.,
Version 1.171.31.7 (release 18-10-2006 CrysAlis171 .NET)
(compiled Oct 18 2006,16:28:17)
Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            COLOURLESS
_exptl_crystal_density_diffrn    1.270
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       NIDDLE
_exptl_crystal_F_000             776
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.30
_exptl_crystal_size_min          0.30
_refine_diff_density_max         0.298
_refine_diff_density_min         -0.396
_refine_diff_density_rms         0.110
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.108
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     253
_refine_ls_number_reflns         3391
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.108
_refine_ls_R_factor_all          0.0991
_refine_ls_R_factor_gt           0.0685
_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^)+(0.1401P)^2^+0.3737P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2078
_refine_ls_wR_factor_ref         0.2580
_reflns_number_gt                2340
_reflns_number_total             3391
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c5ob02400e2.cif
_cod_data_source_block           ss053
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'MONOCLINIC' changed to 'monoclinic'
according to
/usr/data/users/saulius/crontab/automatic-downloads/rss-feeds/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 4268 2015-11-12 08:31:59Z antanas 

 Adding full bibliography for 7154875--7154878.cif.
;
_cod_original_cell_volume        1927.5(3)
_cod_original_sg_symbol_H-M      P2(1)/c
_cod_database_code               7154877