Using nucleophilic substitution reactions to understand how a remote alkyl or alkoxy substituent influences the conformation of eight-membered ring oxocarbenium ions.
Chamberland, Stephen; Woerpel, K. A.; Organic letters 6 (2004) 4739–4741; doi:10.1021/ol047998d

data_1506928
_publ_section_title
;
 Using nucleophilic substitution reactions to understand how a remote
 alkyl or alkoxy substituent influences the conformation of eight-membered
 ring oxocarbenium ions.
;
_journal_issue                   25
_journal_name_full               'Organic letters'
_journal_page_first              4739
_journal_page_last               4741
_journal_paper_doi               10.1021/ol047998d
_journal_volume                  6
_journal_year                    2004
_chemical_formula_sum            'C18 H24 N O3'
_chemical_formula_weight         302.38
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXTL
_cell_angle_alpha                94.2720(10)
_cell_angle_beta                 94.6620(10)
_cell_angle_gamma                95.6630(10)
_cell_formula_units_Z            2
_cell_length_a                   5.2748(3)
_cell_length_b                   10.1002(6)
_cell_length_c                   15.4153(9)
_cell_measurement_temperature    173(2)
_cell_volume                     811.74(8)
_computing_cell_refinement       'Bruker SMART/SAINT'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SHELXTL'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'Bruker SHELXTL'
_computing_structure_solution    'Bruker SHELXTL'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.938
_diffrn_measured_fraction_theta_max 0.938
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0233
_diffrn_reflns_av_sigmaI/netI    0.0269
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            8683
_diffrn_reflns_theta_full        28.38
_diffrn_reflns_theta_max         28.38
_diffrn_reflns_theta_min         2.03
_diffrn_standards_decay_%        '< 1.0'
_diffrn_standards_interval_count 'initial 50 frames recollected'
_diffrn_standards_number         '50 frames'
_exptl_absorpt_coefficient_mu    0.084
_exptl_absorpt_correction_T_max  0.9802
_exptl_absorpt_correction_T_min  0.9689
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.237
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'irregular needle'
_exptl_crystal_F_000             326
_exptl_crystal_size_max          0.38
_exptl_crystal_size_mid          0.30
_exptl_crystal_size_min          0.24
_refine_diff_density_max         0.578
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_refine_ls_extinction_method     none
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_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     295
_refine_ls_number_reflns         3814
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.059
_refine_ls_R_factor_all          0.0627
_refine_ls_R_factor_gt           0.0536
_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^)+(0.1026P)^2^+0.1307P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1419
_refine_ls_wR_factor_ref         0.1522
_reflns_number_gt                3211
_reflns_number_total             3814
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol047998dsi20041026_080507.cif
_cod_data_source_block           kaw37
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Triclinic' changed to 'triclinic'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'none' was changed to '?' - the
value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
;
_cod_original_sg_symbol_H-M      P-1
_cod_database_code               1506928