Strained to the limit: when a cyclobutyl moiety becomes a thermodynamic sink in a protolytic ring-opening of photogenerated oxetanes.
Valiulin, Roman A.; Arisco, Teresa M.; Kutateladze, Andrei G.; Organic letters 12 (2010) 3398–3401; doi:10.1021/ol101297b

data_1503100
_publ_section_title
;
 Strained to the limit: when a cyclobutyl moiety becomes a thermodynamic
 sink in a protolytic ring-opening of photogenerated oxetanes.
;
_journal_issue                   15
_journal_name_full               'Organic letters'
_journal_page_first              3398
_journal_page_last               3401
_journal_paper_doi               10.1021/ol101297b
_journal_volume                  12
_journal_year                    2010
_chemical_formula_moiety         'C18 H21 Cl O2'
_chemical_formula_sum            'C18 H21 Cl O2'
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_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   18.9939(3)
_cell_length_b                   7.06720(10)
_cell_length_c                   21.2043(4)
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_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      28.52
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_cell_volume                     2846.33(8)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
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_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      296(2)
_diffrn_detector_area_resol_mean 8.33
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker D8 APEX II Diffractometer'
_diffrn_measurement_method       '\f and \w scans'
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_diffrn_reflns_theta_max         27.48
_diffrn_reflns_theta_min         1.92
_exptl_absorpt_coefficient_mu    0.271
_exptl_absorpt_correction_T_max  0.9511
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_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.423
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       parallelogram
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_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0626P)^2^+2.0051P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0895
_refine_ls_wR_factor_ref         0.0909
_reflns_number_gt                3140
_reflns_number_total             3261
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol101297b_si_008.cif
_cod_data_source_block           ortho77
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_sg_symbol_H-M      'Pbca '
_cod_database_code               1503100