Application of the Helquist Annulation in Lycopodium Alkaloid Synthesis: Unified Total Syntheses of (-)-8-Deoxyserratinine, (+)-Fawcettimine, and (+)-Lycoflexine
Yu-Rong Yang; Liang Shen; Jiu-Zhong Huang; Tao Xu; Kun Wei; Journal of Organic Chemistry 76 (2011) 3684–3690; doi:10.1021/jo1023188

data_4026275
_publ_section_title
;
 Application of the Helquist Annulation in Lycopodium Alkaloid Synthesis:
 Unified Total Syntheses of (-)-8-Deoxyserratinine, (+)-Fawcettimine, and
 (+)-Lycoflexine
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              3684
_journal_page_last               3690
_journal_paper_doi               10.1021/jo1023188
_journal_volume                  76
_journal_year                    2011
_chemical_formula_sum            'C16 H25 N O2'
_chemical_formula_weight         263.37
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           78
_symmetry_cell_setting           tetragonal
_symmetry_space_group_name_Hall  'P 4cw'
_symmetry_space_group_name_H-M   'P 43'
_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                   8.2499(9)
_cell_length_b                   8.2499(9)
_cell_length_c                   42.596(10)
_cell_measurement_reflns_used    2237
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      28.30
_cell_measurement_theta_min      2.462
_cell_volume                     2899.1(8)
_computing_cell_refinement       'Bruker apex II'
_computing_data_collection       'Bruker apex II'
_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      293(2)
_diffrn_measured_fraction_theta_full 0.976
_diffrn_measured_fraction_theta_max 0.976
_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  0.1627
_diffrn_reflns_av_sigmaI/netI    0.2299
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       47
_diffrn_reflns_limit_l_min       -55
_diffrn_reflns_number            18901
_diffrn_reflns_theta_full        28.30
_diffrn_reflns_theta_max         28.30
_diffrn_reflns_theta_min         1.91
_exptl_absorpt_coefficient_mu    0.078
_exptl_absorpt_correction_T_max  0.9839
_exptl_absorpt_correction_T_min  0.9769
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   Sadabs
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.207
_exptl_crystal_description       block
_exptl_crystal_F_000             1152
_exptl_crystal_size_max          0.21
_exptl_crystal_size_mid          0.16
_exptl_crystal_size_min          0.08
_refine_diff_density_max         0.183
_refine_diff_density_min         -0.176
_refine_diff_density_rms         0.046
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -2(2)
_refine_ls_extinction_coef       0.0058(7)
_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   0.914
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     348
_refine_ls_number_reflns         6448
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.914
_refine_ls_R_factor_all          0.2421
_refine_ls_R_factor_gt           0.0703
_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^)+(0.0357P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1091
_refine_ls_wR_factor_ref         0.1577
_reflns_number_gt                2237
_reflns_number_total             6448
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo1023188_si_002.cif
_cod_data_source_block           2
_cod_database_code               4026275