Selective formation of spiro dihydrofurans and cyclopropanes through unexpected reaction of aldehydes with 1,3-dicarbonyl compounds.
Wang, Guan-Wu; Gao, Jie; Organic letters 11 (2009) 2385–2388; doi:10.1021/ol900451d

data_1503868
_publ_section_title
;
 Selective formation of spiro dihydrofurans and cyclopropanes through
 unexpected reaction of aldehydes with 1,3-dicarbonyl compounds.
;
_journal_issue                   11
_journal_name_full               'Organic letters'
_journal_page_first              2385
_journal_page_last               2388
_journal_paper_doi               10.1021/ol900451d
_journal_volume                  11
_journal_year                    2009
_chemical_formula_sum            'C23 H25 N O6'
_chemical_formula_weight         411.44
_space_group_IT_number           14
_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                 113.93(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   12.800(3)
_cell_length_b                   16.100(3)
_cell_length_c                   11.140(2)
_cell_measurement_temperature    293(2)
_cell_volume                     2098.4(9)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_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  0.0000
_diffrn_reflns_av_sigmaI/netI    0.0443
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            4109
_diffrn_reflns_theta_full        25.99
_diffrn_reflns_theta_max         25.99
_diffrn_reflns_theta_min         1.74
_exptl_absorpt_coefficient_mu    0.094
_exptl_absorpt_correction_T_max  0.9814
_exptl_absorpt_correction_T_min  0.9633
_exptl_crystal_density_diffrn    1.302
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             872
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.30
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.412
_refine_diff_density_min         -0.384
_refine_diff_density_rms         0.088
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.002
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     271
_refine_ls_number_reflns         4109
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.002
_refine_ls_R_factor_all          0.1269
_refine_ls_R_factor_gt           0.0736
_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^)+(0.0600P)^2^+7.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1612
_refine_ls_wR_factor_ref         0.2229
_reflns_number_gt                2573
_reflns_number_total             4109
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol900451d_si_002.cif
_cod_data_source_block           x
_cod_original_cell_volume        2098.4(7)
_cod_database_code               1503868