Unexpected ring expansion of an enantiopure imidazoline carbene ligand.
Pelegrí, Adela Sanchez; Elsegood, Mark R. J.; McKee, Vickie; Weaver, George W.; Organic letters 8 (2006) 3049–3051; doi:10.1021/ol0609917

data_1506053
_publ_section_title
;
 Unexpected ring expansion of an enantiopure imidazoline carbene ligand.
;
_journal_issue                   14
_journal_name_full               'Organic letters'
_journal_page_first              3049
_journal_page_last               3051
_journal_paper_doi               10.1021/ol0609917
_journal_volume                  8
_journal_year                    2006
_chemical_absolute_configuration syn
_chemical_formula_sum            'C24 H40 N2 O'
_chemical_formula_weight         372.58
_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
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   6.5081(13)
_cell_length_b                   11.812(2)
_cell_length_c                   27.375(6)
_cell_measurement_reflns_used    5004
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      27.30
_cell_measurement_theta_min      2.28
_cell_volume                     2104.4(7)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL and local programs'
_computing_structure_refinement  'Bruker SHELXTL'
_computing_structure_solution    'Bruker SHELXTL'
_diffrn_ambient_temperature      150(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Bruker SMART 1000 CCD diffractometer'
_diffrn_measurement_method       '\w rotation with narrow frames'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0705
_diffrn_reflns_av_sigmaI/netI    0.0795
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       32
_diffrn_reflns_limit_l_min       -32
_diffrn_reflns_number            14007
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         1.88
_diffrn_standards_decay_%        0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.071
_exptl_absorpt_correction_T_max  0.994
_exptl_absorpt_correction_T_min  0.974
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS v2.03, Sheldrick, G.M.'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.176
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             824
_exptl_crystal_size_max          0.38
_exptl_crystal_size_mid          0.27
_exptl_crystal_size_min          0.09
_refine_diff_density_max         0.654
_refine_diff_density_min         -0.367
_refine_diff_density_rms         0.086
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -3(5)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.086
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     250
_refine_ls_number_reflns         3681
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.086
_refine_ls_R_factor_all          0.1109
_refine_ls_R_factor_gt           0.0974
_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^)+(0.0806P)^2^+6.5593P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2399
_refine_ls_wR_factor_ref         0.2486
_reflns_number_gt                3084
_reflns_number_total             3681
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            ol0609917si20060426_024732.cif
_cod_data_source_block           10
_cod_original_cell_volume        2104.3(7)
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               1506053