An entry to 2-(cyclobut-1-en-1-yl)-1<i>H</i>-indoles through a cyclobutenylation/deprotection cascade.
Natho, Philipp; Yang, Zeyu; Allen, Lewis A. T.; Rey, Juliette; White, Andrew J. P.; Parsons, Philip J.; Organic & biomolecular chemistry 19 (2021) 4048–4053; doi:10.1039/d1ob00430a

data_7158028
_publ_section_title
;
 An entry to 2-(cyclobut-1-en-1-yl)-1<i>H</i>-indoles through a
 cyclobutenylation/deprotection cascade.
;
_journal_issue                   18
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              4048
_journal_page_last               4053
_journal_paper_doi               10.1039/d1ob00430a
_journal_volume                  19
_journal_year                    2021
_chemical_formula_moiety         'C13 H13 N O'
_chemical_formula_sum            'C13 H13 N O'
_chemical_formula_weight         199.24
_space_group_crystal_system      orthorhombic
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_space_group_name_Hall           '-P 2ac 2ab'
_space_group_name_H-M_alt        'P b c a'
_atom_sites_solution_hydrogens   mixed
_audit_creation_method           SHELXL-2018/3
_audit_update_record
;
2021-01-21 deposited with the CCDC.	2021-04-14 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            8
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_cell_length_c                   17.8360(15)
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_cell_measurement_theta_min      3.5060
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_computing_cell_refinement       'CrysAlisPro, Rigaku OD'
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_computing_publication_material  'CIFTAB-2014 (Sheldrick, 2017)'
_computing_structure_refinement  'SHELXL-2018/3 (Sheldrick, 2018)'
_computing_structure_solution    'SHELXS-2014 (Sheldrick, 2017)'
_diffrn_ambient_temperature      173(2)
_diffrn_detector_area_resol_mean 16.0382
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.863
_diffrn_measurement_device_type  'Agilent Xcalibur 3 E'
_diffrn_measurement_method       'omega scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0328
_diffrn_reflns_av_unetI/netI     0.0586
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.863
_diffrn_reflns_limit_h_max       16
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            2325
_diffrn_reflns_point_group_measured_fraction_full 0.999
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_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         28.136
_diffrn_reflns_theta_min         2.284
_diffrn_source                   'Enhance (Mo) X-ray Source'
_exptl_absorpt_coefficient_mu    0.080
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_exptl_absorpt_correction_T_min  0.976
_exptl_absorpt_correction_type   analytical
_exptl_absorpt_process_details
; 
CrysAlisPro 1.171.39.46 (Rigaku Oxford Diffraction, 2018) 
Analytical numeric absorption correction using a multifaceted crystal 
model based on expressions derived by R.C. Clark & J.S. Reid. 
(Clark, R. C. & Reid, J. S. (1995). Acta Cryst. A51, 887-897) 
Empirical absorption correction using spherical harmonics, 
implemented in SCALE3 ABSPACK scaling algorithm. 
;
_exptl_crystal_colour            Colourless
_exptl_crystal_density_diffrn    1.266
_exptl_crystal_description       'blocky needles'
_exptl_crystal_F_000             848
_exptl_crystal_size_max          0.644
_exptl_crystal_size_mid          0.223
_exptl_crystal_size_min          0.074
_refine_diff_density_max         0.155
_refine_diff_density_min         -0.179
_refine_diff_density_rms         0.037
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.883
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     142
_refine_ls_number_reflns         2325
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.883
_refine_ls_R_factor_all          0.0916
_refine_ls_R_factor_gt           0.0415
_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^)+(0.0508P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0860
_refine_ls_wR_factor_ref         0.0951
_reflns_Friedel_coverage         0.000
_reflns_number_gt                1294
_reflns_number_total             2325
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d1ob00430a2.cif
_cod_data_source_block           2d
_cod_depositor_comments          'Adding full bibliography for 7158028.cif.'
_cod_database_code               7158028
_shelx_shelxl_version_number     2018/3
_shelx_res_checksum              12612