Total Synthesis of (±)-α-Isosparteine, (±)-β-Isosparteine, and (±)-Sparteine from a Common Tetraoxobispidine Intermediate
Neil R. Norcross; John P. Melbardis; Margarita Ferris Solera; Mark A. Sephton; Colin Kilner; Lev N. Zakharov; Peter C. Astles; Stuart L. Warriner; Paul R. Blakemore; Journal of Organic Chemistry 73 (2008) 7939–7951; doi:10.1021/jo8013512

data_4023737
_publ_section_title
;
 Total Synthesis of (+-)-\a-Isosparteine, (+-)-\b-Isosparteine, and
 (+-)-Sparteine from a Common Tetraoxobispidine Intermediate
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              7939
_journal_page_last               7951
_journal_paper_doi               10.1021/jo8013512
_journal_volume                  73
_journal_year                    2008
_chemical_formula_moiety         'C27 H30 N2 O3'
_chemical_formula_sum            'C27 H30 N2 O3'
_chemical_formula_weight         430.53
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 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                 103.7750(13)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   11.9751(2)
_cell_length_b                   9.7313(2)
_cell_length_c                   20.2462(3)
_cell_measurement_reflns_used    18637
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      27.48
_cell_measurement_theta_min      1.00
_cell_volume                     2291.50(7)
_computing_cell_refinement       'DENZO-SMN (Otwinowski & Minor, 1996)'
_computing_data_collection       'COLLECT (Nonius, 2004)'
_computing_data_reduction
;
DENZO-SMN and COLLECT (Otwinowski & Minor, 1996)
;
_computing_molecular_graphics
;
ORTEP-III Version 1.08 (Farrugia, 2005)
;
_computing_publication_material
;
enCIFer: A program for viewing, editing and visualising CIFs. 
F. H. Allen, O. Johnson, G. P. Shields, B. R. Smith, M. Towler, 
J. Applied Cryst., 37, 331-334, 2004
;
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution
;
SIR92
Altomare, A.; Burla, M. C.; Camalli, G.; Cascarano, G.; 
Giacovazzo, C.; Guagliardi, A.; Polidori, G. 
J. Appl. Cryst. 1994, 27, 435-436. 
;
_diffrn_ambient_temperature      150(2)
_diffrn_detector_area_resol_mean 9
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type
;
Nonius KappaCCD area-detector diffractometer
;
_diffrn_measurement_method
;       
phi and omega scans to fill the asymmetric unit
;
_diffrn_radiation_detector       'CCD plate'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0858
_diffrn_reflns_av_sigmaI/netI    0.0440
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            34210
_diffrn_reflns_theta_full        26.00
_diffrn_reflns_theta_max         26.00
_diffrn_reflns_theta_min         2.77
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.081
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.248
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             920
_exptl_crystal_size_max          0.31
_exptl_crystal_size_mid          0.26
_exptl_crystal_size_min          0.14
_refine_diff_density_max         0.246
_refine_diff_density_min         -0.335
_refine_diff_density_rms         0.064
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.067
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     290
_refine_ls_number_reflns         4487
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.067
_refine_ls_R_factor_all          0.0650
_refine_ls_R_factor_gt           0.0440
_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^)+(0.0629P)^2^+0.2703P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1060
_refine_ls_wR_factor_ref         0.1183
_reflns_number_gt                3378
_reflns_number_total             4487
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo8013512_si_008.cif
_cod_data_source_block           cmpd56
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               4023737