Alder-Ene Reactions Driven by High Steric Strain and Bond Angle Distortion to Form Benzocyclobutenes
Gupta, Saswata; Lin, Yongjia; Xia, Yuanzhi; Wink, Donald; Lee, Daesung; Chemical Science  (2019) –; doi:10.1039/C8SC04277B

data_1550379
_publ_section_title
;
 Alder-Ene Reactions Driven by High Steric Strain and Bond Angle
 Distortion to Form Benzocyclobutenes
;
_journal_name_full               'Chemical Science'
_journal_paper_doi               10.1039/C8SC04277B
_journal_year                    2019
_chemical_absolute_configuration unk
_chemical_formula_sum            'C21 H24 O4'
_chemical_formula_weight         340.40
_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
_audit_update_record
;
2018-05-17 deposited with the CCDC.
2018-12-19 downloaded from the CCDC.
;
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   6.2996(4)
_cell_length_b                   14.6723(11)
_cell_length_c                   19.1704(13)
_cell_measurement_reflns_used    9703
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      21.7459
_cell_measurement_theta_min      2.9687
_cell_volume                     1771.9(2)
_computing_cell_refinement       'SAINT (Bruker)'
_computing_data_collection       'SMART (Bruker)'
_computing_data_reduction        'SAINT (Bruker)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.974
_diffrn_measured_fraction_theta_max 0.974
_diffrn_measurement_device_type  CCD
_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  0.0495
_diffrn_reflns_av_sigmaI/netI    0.0405
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            23114
_diffrn_reflns_theta_full        24.79
_diffrn_reflns_theta_max         24.79
_diffrn_reflns_theta_min         1.75
_exptl_absorpt_coefficient_mu    0.087
_exptl_absorpt_correction_T_max  0.9828
_exptl_absorpt_correction_T_min  0.9659
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.276
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             728
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.30
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.178
_refine_diff_density_min         -0.176
_refine_diff_density_rms         0.036
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.6(15)
_refine_ls_extinction_coef       0.029(4)
_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   0.869
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     233
_refine_ls_number_reflns         2927
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.869
_refine_ls_R_factor_all          0.0682
_refine_ls_R_factor_gt           0.0411
_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^)+(0.1000P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1031
_refine_ls_wR_factor_ref         0.1171
_reflns_number_gt                2282
_reflns_number_total             2927
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c8sc04277b2.cif
_cod_data_source_block           Compound2o
_cod_database_code               1550379
_publ_contact_phone              312-413-7383
_publ_contact_fax                312-996-0431
_publ_contact_email              dwink@uic.edu