Kinetics and Mechanism of Ketone Enolization Mediated by Magnesium Bis(hexamethyldisilazide)
Xuyang He; J. Jacob Morris; Bruce C. Noll; Seth N. Brown; Kenneth W. Henderson; Journal of the American Chemical Society 128 (2006) 13599–13610; doi:10.1021/ja064927w

data_4110976
_publ_contact_author_address
;University of Notre Dame
Department of Chemistry
Notre Dame, IN 46556-5670
;
_publ_contact_author_email       khenders@nd.edu
_publ_contact_author_fax         574.631.6652
_publ_contact_author_name        'Kenneth W. Henderson'
_publ_contact_author_phone       574.631.8025
_publ_section_title
;
 Kinetics and Mechanism of Ketone Enolization Mediated by Magnesium
 Bis(hexamethyldisilazide)
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              13599
_journal_page_last               13610
_journal_paper_doi               10.1021/ja064927w
_journal_volume                  128
_journal_year                    2006
_chemical_compound_source        synthesized
_chemical_formula_moiety         'C23 H50 Mg N2 O Si4'
_chemical_formula_sum            'C23 H50 Mg N2 O Si4'
_chemical_formula_weight         507.32
_chemical_name_common            'Mg(HMDS)2 Pivalophenone'
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_Int_Tables_number      14
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_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                 100.694(1)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.3655(2)
_cell_length_b                   20.6214(6)
_cell_length_c                   18.7658(5)
_cell_measurement_reflns_used    9255
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      31.5136
_cell_measurement_theta_min      2.5186
_cell_volume                     3181.03(15)
_computing_cell_refinement       'APEX2/SAINT (Bruker, 2004)'
_computing_data_collection       'APEX2 (Bruker, 2004)'
_computing_data_reduction        'SAINT/XPREP (Bruker, 2004; Sheldrick, 2003)'
_computing_molecular_graphics    'XP (Sheldrick, 1998)'
_computing_publication_material  'XCIF (Sheldrick, 2001)/enCIFer (CCDC, 2004)'
_computing_structure_refinement  'XL (Sheldrick, 2001)'
_computing_structure_solution    'XS (Sheldrick, 2001)'
_diffrn_ambient_temperature      100(2)
_diffrn_detector_area_resol_mean 8.33
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker x8-ApexII CCD diffractometer'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0367
_diffrn_reflns_av_sigmaI/netI    0.0201
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       30
_diffrn_reflns_limit_k_min       -30
_diffrn_reflns_limit_l_max       27
_diffrn_reflns_limit_l_min       -26
_diffrn_reflns_number            116269
_diffrn_reflns_theta_full        31.56
_diffrn_reflns_theta_max         31.56
_diffrn_reflns_theta_min         1.48
_diffrn_source                   'fine-focus sealed tube'
_diffrn_source_type              'Siemens KFFMO2K-90'
_exptl_absorpt_coefficient_mu    0.223
_exptl_absorpt_correction_T_max  0.9652
_exptl_absorpt_correction_T_min  0.9044
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;Blessing, R. H. (1995) Acta Cryst. A51, 33-38.

Sheldrick, G. M. (2004) SADABS. University of G\"ottingen, Germany.
;
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.059
_exptl_crystal_description       plate
_exptl_crystal_F_000             1112
_exptl_crystal_recrystallization_method
'crystallized on cooling in hexane solution from 20 \%C to 0 \%C.'
_exptl_crystal_size_max          0.46
_exptl_crystal_size_mid          0.43
_exptl_crystal_size_min          0.16
_refine_diff_density_max         0.459
_refine_diff_density_min         -0.176
_refine_diff_density_rms         0.046
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.028
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     298
_refine_ls_number_reflns         10635
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.028
_refine_ls_R_factor_all          0.0389
_refine_ls_R_factor_gt           0.0286
_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^)+(0.0367P)^2^+0.9217P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0734
_refine_ls_wR_factor_ref         0.0791
_reflns_number_gt                8965
_reflns_number_total             10635
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja064927wsi20060711_044509.cif
_cod_data_source_block           bcn261
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               4110976