Synthesis of the guaianolide ring system via cycloaddition of a bicyclic carbonyl ylide with allyl propiolate.
Navickas, Vaidotas; Ushakov, Dmitry B.; Maier, Martin E.; Ströbele, Markus; Meyer, H-Jürgen; Organic letters 12 (2010) 3418–3421; doi:10.1021/ol1012185

data_1503077
_publ_section_title
;
 Synthesis of the guaianolide ring system via cycloaddition of a bicyclic
 carbonyl ylide with allyl propiolate.
;
_journal_issue                   15
_journal_name_full               'Organic letters'
_journal_page_first              3418
_journal_page_last               3421
_journal_paper_doi               10.1021/ol1012185
_journal_volume                  12
_journal_year                    2010
_chemical_absolute_configuration syn
_chemical_formula_sum            'C15 H24 O3'
_chemical_formula_weight         252.34
_chemical_name_common            guaianolide
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_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            4
_cell_length_a                   7.387(1)
_cell_length_b                   11.854(1)
_cell_length_c                   15.835(2)
_cell_measurement_reflns_used    8000
_cell_measurement_temperature    210(2)
_cell_measurement_theta_max      26.03
_cell_measurement_theta_min      2.57
_cell_volume                     1386.6(3)
_computing_cell_refinement       'STOE IPDS SOFTWARE'
_computing_data_collection       'STOE IPDS SOFTWARE'
_computing_data_reduction        'STOE IPDS SOFTWARE'
_computing_molecular_graphics    'Diamond 3.1'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      210(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'STOE IPDS I'
_diffrn_measurement_method       Oscillation
_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  0.0586
_diffrn_reflns_av_sigmaI/netI    0.0420
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            18938
_diffrn_reflns_theta_full        26.03
_diffrn_reflns_theta_max         26.03
_diffrn_reflns_theta_min         2.57
_diffrn_standards_decay_%        0.001
_exptl_absorpt_coefficient_mu    0.082
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            white
_exptl_crystal_density_diffrn    1.209
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             552
_exptl_crystal_size_max          0.2
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.227
_refine_diff_density_min         -0.148
_refine_diff_density_rms         0.049
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.937
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     249
_refine_ls_number_reflns         2728
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.937
_refine_ls_R_factor_all          0.0526
_refine_ls_R_factor_gt           0.0405
_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^)+(0.0494P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0801
_refine_ls_wR_factor_ref         0.0833
_reflns_number_gt                2176
_reflns_number_total             2728
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol1012185_si_003.cif
_cod_data_source_block           EnglerinAanalog
_cod_original_cell_volume        1386.7(3)
_cod_database_code               1503077