A practical synthesis of (+/-)-alpha-isosparteine from a tetraoxobispidine core.
Blakemore, Paul R.; Kilner, Colin; Norcross, Neil R.; Astles, Peter C.; Organic letters 7 (2005) 4721–4724; doi:10.1021/ol0519184

data_1506722
_publ_section_title
;
 A practical synthesis of (+/-)-alpha-isosparteine from a
 tetraoxobispidine core.
;
_journal_issue                   21
_journal_name_full               'Organic letters'
_journal_page_first              4721
_journal_page_last               4724
_journal_paper_doi               10.1021/ol0519184
_journal_volume                  7
_journal_year                    2005
_chemical_formula_moiety         'C15 H18 N2 O4'
_chemical_formula_sum            'C15 H18 N2 O4'
_chemical_formula_weight         290.31
_space_group_IT_number           61
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2ab'
_symmetry_space_group_name_H-M   'P b c a'
_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            8
_cell_length_a                   8.5596(8)
_cell_length_b                   11.4819(12)
_cell_length_c                   26.250(3)
_cell_measurement_reflns_used    5282
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      25.43
_cell_measurement_theta_min      1.00
_cell_volume                     2579.9(5)
_computing_cell_refinement
;
APEX 2 software, Bruker Nonius 2004 
;
_computing_data_collection
;
APEX 2 software, Bruker Nonius 2004 
;
_computing_data_reduction
;
SAINT - Bruker Integration program embedded in
APEX 2 software, Bruker Nonius 2004 
;
_diffrn_ambient_temperature      150(2)
_diffrn_detector_area_resol_mean
;
120 microns
;
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type
;
Mach3 kappa-type 4-circle goniostat.
;
_diffrn_measurement_method       'rotation images'
_diffrn_radiation_detector       'Apex camera'
_diffrn_radiation_monochromator
;
graphite model mounted in "parallel" mode
;
_diffrn_radiation_source
;
Bruker Nonius FR591 rotating anode generator
;
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0478
_diffrn_reflns_av_sigmaI/netI    0.0253
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       31
_diffrn_reflns_limit_l_min       -31
_diffrn_reflns_number            29091
_diffrn_reflns_theta_full        25.43
_diffrn_reflns_theta_max         25.43
_diffrn_reflns_theta_min         2.84
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.109
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.495
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             1232
_exptl_crystal_size_max          0.16
_exptl_crystal_size_mid          0.13
_exptl_crystal_size_min          0.02
_refine_diff_density_max         0.235
_refine_diff_density_min         -0.215
_refine_diff_density_rms         0.043
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.055
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     192
_refine_ls_number_reflns         2370
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.055
_refine_ls_R_factor_all          0.0487
_refine_ls_R_factor_gt           0.0336
_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^)+(0.0451P)^2^+0.7888P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0807
_refine_ls_wR_factor_ref         0.0869
_reflns_number_gt                1870
_reflns_number_total             2370
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol0519184si20050809_053137.cif
_cod_data_source_block           cmpd9
_cod_database_code               1506722