Methylation of Sydnone N-Oxides: Kinetic and Thermodynamic Control in the Alkylation Site of an Electron-Rich Heterocycle
D. Scott Bohle; Lindsey E. McQuade; Inna Perepichka; Lijuan Zhang; Journal of Organic Chemistry 72 (2007) 3625–3631; doi:10.1021/jo062235k

data_4022718
_publ_section_title
;
 Methylation of Sydnone N-Oxides: Kinetic and Thermodynamic
 Control in the Alkylation Site of an Electron-Rich Heterocycle
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              3625
_journal_page_last               3631
_journal_paper_doi               10.1021/jo062235k
_journal_volume                  72
_journal_year                    2007
_chemical_formula_sum            'C5 H6 N2 O5'
_chemical_formula_weight         174.12
_chemical_name_systematic
; 
 4-methylcarboxy2-methyl-3-sydnone N-oxide 
;
_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                   5.0184(7)
_cell_length_b                   7.3717(10)
_cell_length_c                   18.440(2)
_cell_measurement_reflns_used    2999
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      26.79
_cell_measurement_theta_min      2.98
_cell_volume                     682.18(16)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.952
_diffrn_measured_fraction_theta_max 0.952
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.091
_diffrn_reflns_av_sigmaI/netI    0.1271
_diffrn_reflns_limit_h_max       4
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -23
_diffrn_reflns_number            3211
_diffrn_reflns_theta_full        26.79
_diffrn_reflns_theta_max         26.79
_diffrn_reflns_theta_min         2.98
_exptl_absorpt_coefficient_mu    0.154
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.695
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    none
_exptl_crystal_description       flake
_exptl_crystal_F_000             360
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.407
_refine_diff_density_min         -0.366
_refine_diff_density_rms         0.090
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.6(11)
_refine_ls_extinction_coef       0.015(10)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   0.970
_refine_ls_hydrogen_treatment    none
_refine_ls_matrix_type           full
_refine_ls_number_parameters     110
_refine_ls_number_reflns         1321
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.970
_refine_ls_R_factor_all          0.0608
_refine_ls_R_factor_gt           0.0603
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1000P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1333
_refine_ls_wR_factor_ref         0.1341
_reflns_number_gt                1298
_reflns_number_total             1321
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo062235ksi20061031_122703.cif
_cod_data_source_block           KineticIsomer
_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 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 

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_database_code               4022718