(\±)-trans,cis-4-Hydroxy-5,6-di-O-isopropylidenecyclohex-2-ene-1-one: Synthesis and Facile Dimerization to Decahydrodibenzofurans
Victoria L. Paddock; Robert J. Phipps; Almudena Conde-Angulo; Araceli Blanco-Martin; Carles Giró-Mañas; Laetitia J. Martin; Andrew J. P. White; Alan C. Spivey; Journal of Organic Chemistry 76 (2011) 1483–1486; doi:10.1021/jo102314w

data_4026091
_publ_section_title
;
 (\+-)-trans,cis-4-Hydroxy-5,6-di-O-isopropylidenecyclohex-2-ene-1-one:
 Synthesis and Facile Dimerization to Decahydrodibenzofurans
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              1483
_journal_page_last               1486
_journal_paper_doi               10.1021/jo102314w
_journal_volume                  76
_journal_year                    2011
_chemical_formula_moiety         'C9 H14 Br2 O2'
_chemical_formula_sum            'C9 H14 Br2 O2'
_chemical_formula_weight         314.02
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                95.640(8)
_cell_angle_beta                 97.798(9)
_cell_angle_gamma                110.869(13)
_cell_formula_units_Z            2
_cell_length_a                   7.0842(10)
_cell_length_b                   9.0032(13)
_cell_length_c                   9.5389(6)
_cell_measurement_reflns_used    2569
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      32.7702
_cell_measurement_theta_min      3.0031
_cell_volume                     556.12(13)
_computing_cell_refinement       'CrysAlis RED, Oxford Diffraction Ltd'
_computing_data_collection       'CrysAlis CCD, Oxford Diffraction Ltd'
_computing_data_reduction        'CrysAlis RED, Oxford Diffraction Ltd'
_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      296(2)
_diffrn_detector_area_resol_mean 15.9825
_diffrn_measured_fraction_theta_full 0.987
_diffrn_measured_fraction_theta_max 0.886
_diffrn_measurement_device_type  'OD Xcalibur 3'
_diffrn_measurement_method       'omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Enhance (Mo) X-ray Source'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0261
_diffrn_reflns_av_sigmaI/netI    0.0752
_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       14
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            6459
_diffrn_reflns_theta_full        31.00
_diffrn_reflns_theta_max         32.83
_diffrn_reflns_theta_min         3.01
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    7.256
_exptl_absorpt_correction_T_max  0.232
_exptl_absorpt_correction_T_min  0.118
_exptl_absorpt_correction_type   analytical
_exptl_absorpt_process_details
; 
CrysAlisPro, Oxford Diffraction Ltd., 
Version 1.171.33.48 (release 15-09-2009 CrysAlis171 .NET) 
(compiled Sep 15 2009,11:49:04) 
Analytical numeric absorption correction using a multifaceted crystal 
model based on expressions derived by R.C. Clark & J.S. Reid. 
(Clark, R. C. & Reid, J. S. (1995). Acta Cryst. A51, 887-897) 
;
_exptl_crystal_colour            Colourless
_exptl_crystal_density_diffrn    1.875
_exptl_crystal_description       blocks
_exptl_crystal_F_000             308
_exptl_crystal_size_max          0.53
_exptl_crystal_size_mid          0.40
_exptl_crystal_size_min          0.28
_refine_diff_density_max         0.615
_refine_diff_density_min         -0.597
_refine_diff_density_rms         0.086
_refine_ls_extinction_coef       0.207(3)
_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   0.839
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     119
_refine_ls_number_reflns         3660
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.839
_refine_ls_R_factor_all          0.0727
_refine_ls_R_factor_gt           0.0315
_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^)+(0.0295P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0602
_refine_ls_wR_factor_ref         0.0635
_reflns_number_gt                1964
_reflns_number_total             3660
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo102314w_si_002_1.cif
_cod_data_source_block           7
_cod_database_code               4026091