Facilitating access to the most easily ionized molecule: an improved synthesis of the key intermediate, W2(hpp)4Cl2, and related compounds.
Cotton, F. Albert; Donahue, James P.; Gruhn, Nadine E.; Lichtenberger, Dennis L.; Murillo, Carlos A.; Timmons, Daren J.; Van Dorn, Laura O.; Villagrán, Dino; Wang, Xiaoping; Inorganic chemistry 45 (2006) 201–213; doi:10.1021/ic0515709

data_4340252
_publ_section_title
;
 Facilitating access to the most easily ionized molecule: an improved
 synthesis of the key intermediate, W2(hpp)4Cl2, and related compounds.
;
_journal_issue                   1
_journal_name_full               'Inorganic chemistry'
_journal_page_first              201
_journal_page_last               213
_journal_paper_doi               10.1021/ic0515709
_journal_volume                  45
_journal_year                    2006
_chemical_formula_moiety         'C18 H26 N6 O4 W'
_chemical_formula_sum            'C18 H26 N6 O4 W'
_chemical_formula_weight         574.30
_chemical_name_systematic
;
 Tungsten(0) bis(1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidinate)
 tetra(carbonyl)
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_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                 91.280(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.0954(9)
_cell_length_b                   14.7876(17)
_cell_length_c                   17.043(2)
_cell_measurement_reflns_used    9671
_cell_measurement_temperature    193(2)
_cell_measurement_theta_max      27.5425
_cell_measurement_theta_min      2.3905
_cell_volume                     2039.7(4)
_computing_cell_refinement       SAINT
_computing_data_collection       SMART
_computing_data_reduction        SAINT
_computing_molecular_graphics    'SHELXTL V. 5.03 (Siemens, 1994)'
_computing_publication_material  CIFTAB
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      193(2)
_diffrn_measured_fraction_theta_full 0.986
_diffrn_measured_fraction_theta_max 0.986
_diffrn_measurement_device       'Bruker SMART 1000'
_diffrn_measurement_device_type  'area detector'
_diffrn_measurement_method       'omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'normal-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0161
_diffrn_reflns_av_sigmaI/netI    0.0181
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            13983
_diffrn_reflns_theta_full        27.56
_diffrn_reflns_theta_max         27.56
_diffrn_reflns_theta_min         1.82
_diffrn_standards_number         'none (area detector data)'
_exptl_absorpt_coefficient_mu    5.701
_exptl_absorpt_correction_T_max  0.5089
_exptl_absorpt_correction_T_min  0.3878
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.870
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1128
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.15
_exptl_crystal_size_min          0.14
_refine_diff_density_max         0.434
_refine_diff_density_min         -0.631
_refine_diff_density_rms         0.077
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.032
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     366
_refine_ls_number_reflns         4652
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.032
_refine_ls_R_factor_all          0.0178
_refine_ls_R_factor_gt           0.0149
_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^)+(0.0193P)^2^+0.6187P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0352
_refine_ls_wR_factor_ref         0.0364
_reflns_number_gt                4221
_reflns_number_total             4652
_reflns_threshold_expression     I>2sigma(I)
_cod_data_source_file            ic0515709si20050914_104451.cif
_cod_data_source_block           cmpd1b
_cod_depositor_comments
;
The following automatic conversions were performed:

'_geom_bond_publ_flag' value 'Y' changed to 'y' according to
/usr/data/users/saulius/automatic-downloads/retrospective/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26 (16
times).

'_geom_bond_publ_flag' value 'N' changed to 'n' according to
/usr/data/users/saulius/automatic-downloads/retrospective/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26 (16
times).

'_geom_angle_publ_flag' value 'Y' changed to 'y' according
to
/usr/data/users/saulius/automatic-downloads/retrospective/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26 (39
times).

'_geom_angle_publ_flag' value 'N' changed to 'n' according
to
/usr/data/users/saulius/automatic-downloads/retrospective/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26 (12
times).

Automatic conversion script
Id: cif_fix_values 2281 2013-09-26 08:29:07Z andrius 
;
_cod_database_code               4340252