NHC-Catalyzed Formal [2+2] Annulations of Allenoates for the Synthesis of Substituted Oxetanes.
Lopez, Susana S.; Jaworski, Ashley A.; Scheidt, Karl A.; The Journal of organic chemistry 83 (2018) 14637–14645; doi:10.1021/acs.joc.8b02464

data_4035672
_publ_section_title
;
 NHC-Catalyzed Formal [2+2] Annulations of Allenoates for the Synthesis of
 Substituted Oxetanes.
;
_journal_issue                   23
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              14637
_journal_page_last               14645
_journal_paper_doi               10.1021/acs.joc.8b02464
_journal_volume                  83
_journal_year                    2018
_chemical_formula_moiety         'C15 H15 F3 O3'
_chemical_formula_sum            'C15 H15 F3 O3'
_chemical_formula_weight         300.27
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2ybc'
_space_group_name_H-M_alt        'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     dual
_audit_creation_date             2018-06-27
_audit_creation_method
;
Olex2 1.2
(compiled 2018.05.29 svn.r3508 for OlexSys, GUI svn.r5506)
;
_cell_angle_alpha                90
_cell_angle_beta                 100.548(3)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   10.0575(3)
_cell_length_b                   7.5881(3)
_cell_length_c                   18.9210(6)
_cell_measurement_reflns_used    9878
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      66.582
_cell_measurement_theta_min      4.472
_cell_volume                     1419.60(8)
_computing_cell_refinement       'SAINT V8.38A (?, 2016)'
_computing_data_collection       'APEX2 V2014.11-0 (Bruker, 2014)'
_computing_data_reduction        'SAINT V8.38A (?, 2016)'
_computing_molecular_graphics    'Olex2 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 (Dolomanov et al., 2009)'
_computing_structure_refinement  'ShelXL (Sheldrick, 2015)'
_computing_structure_solution    'ShelXT (Sheldrick, 2015)'
_diffrn_ambient_temperature      100.15
_diffrn_detector_area_resol_mean 8
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_diffrn_measurement_device_type  'Bruker Kappa APEX CCD area detector'
_diffrn_measurement_method       '\w and \f scans'
_diffrn_radiation_monochromator  'Quazar optics'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0411
_diffrn_reflns_av_unetI/netI     0.0440
_diffrn_reflns_Laue_measured_fraction_full 0.993
_diffrn_reflns_Laue_measured_fraction_max 0.993
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            10988
_diffrn_reflns_point_group_measured_fraction_full 0.993
_diffrn_reflns_point_group_measured_fraction_max 0.993
_diffrn_reflns_theta_full        66.564
_diffrn_reflns_theta_max         66.564
_diffrn_reflns_theta_min         4.472
_diffrn_source                   microsource
_exptl_absorpt_coefficient_mu    1.061
_exptl_absorpt_correction_T_max  0.7528
_exptl_absorpt_correction_T_min  0.6375
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
'SADABS-2016/2 (Bruker,2016/2) was used for absorption correction. wR2(int) was 0.0795 before and 0.0596 after correction. The Ratio of minimum to maximum transmission is 0.8468. The \l/2 correction factor is Not present.'
_exptl_crystal_colour            colourless
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.405
_exptl_crystal_description       block
_exptl_crystal_F_000             624
_exptl_crystal_recrystallization_method
'The material was recrystallised from --- by as supplied'
_exptl_crystal_size_max          0.604
_exptl_crystal_size_mid          0.259
_exptl_crystal_size_min          0.152
_refine_diff_density_max         0.280
_refine_diff_density_min         -0.259
_refine_diff_density_rms         0.059
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.080
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     248
_refine_ls_number_reflns         2470
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.080
_refine_ls_R_factor_all          0.0465
_refine_ls_R_factor_gt           0.0455
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0497P)^2^+0.7351P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1165
_refine_ls_wR_factor_ref         0.1174
_reflns_Friedel_coverage         0.000
_reflns_number_gt                2386
_reflns_number_total             2470
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            jo8b02464_si_002.cif
_cod_data_source_block           cx1326_pl
_cod_database_code               4035672
_shelx_shelxl_version_number     2018/1
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2. Others
 Sof(O2A)=Sof(O3A)=Sof(C10A)=Sof(H10A)=Sof(C11A)=Sof(C12A)=Sof(H12C)=Sof(H12D)=
 Sof(C13A)=Sof(H13D)=Sof(H13E)=Sof(H13F)=1-FVAR(1)
 Sof(O2)=Sof(O3)=Sof(C10)=Sof(H10)=Sof(C11)=Sof(C12)=Sof(H12A)=Sof(H12B)=
 Sof(C13)=Sof(H13A)=Sof(H13B)=Sof(H13C)=FVAR(1)
3.a Ternary CH refined with riding coordinates:
 C8(H8)
3.b Secondary CH2 refined with riding coordinates:
 C12(H12A,H12B), C12A(H12C,H12D)
3.c Aromatic/amide H refined with riding coordinates:
 C2(H2), C3(H3), C4(H4), C5(H5), C6(H6), C10(H10), C10A(H10A)
3.d Idealised Me refined as rotating group:
 C13(H13A,H13B,H13C), C13A(H13D,H13E,H13F), C15(H15A,H15B,H15C)
;
_shelx_res_checksum              42597
_shelx_hkl_checksum              52141
_olex2_date_sample_data_collection 2018-06-26
_olex2_date_sample_submission    2018-06-25
_olex2_diffrn_ambient_temperature_device 'Oxford Cryosystems'
_olex2_exptl_crystal_mounting_method
'The crystal was mounted on a MITIGEN holder in Paratone oil'
_olex2_submission_original_sample_id cx1326
_olex2_submission_special_instructions 'No special instructions were received'