Total Synthesis of (+)-Cymbodiacetal: A Re-evaluation of the Biomimetic Route
Maliha Uroos; William Lewis; Alexander J. Blake; Christopher J. Hayes; Journal of Organic Chemistry 75 (2010) 8465–8470; doi:10.1021/jo101691n

data_4025871
_publ_section_title
;
 Total Synthesis of (+)-Cymbodiacetal: A Re-evaluation of the Biomimetic
 Route
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              8465
_journal_page_last               8470
_journal_paper_doi               10.1021/jo101691n
_journal_volume                  75
_journal_year                    2010
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C20 H30 O4, C H Cl3 '
_chemical_formula_sum            'C21 H31 Cl3 O4'
_chemical_formula_weight         453.81
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           'enCIFer editing of SHELXL-97 created file'
_cell_angle_alpha                90.00
_cell_angle_beta                 97.847(4)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   5.9089(15)
_cell_length_b                   17.868(5)
_cell_length_c                   10.642(3)
_cell_measurement_reflns_used    1830
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      26.81
_cell_measurement_theta_min      2.24
_cell_volume                     1113.1(5)
_computing_cell_refinement       'Bruker SAINT version 6.36A (Bruker, 2002)'
_computing_data_collection       'Bruker SMART version 5.625 (Bruker, 2001)'
_computing_data_reduction        'Bruker SAINT; SHELXTL (Sheldrick, 2008)'
_computing_molecular_graphics    ' ? '
_computing_publication_material  'enCIFer(Allen et al.,2004);PLATON(Spek,2003)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHEXTL (Sheldrick, 2008)'
_diffrn_ambient_temperature      150(2)
_diffrn_detector_area_resol_mean 8.366
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker SMART APEX CCD area detector'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0641
_diffrn_reflns_av_sigmaI/netI    0.0971
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       21
_diffrn_reflns_limit_k_min       -21
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            8123
_diffrn_reflns_theta_full        25.04
_diffrn_reflns_theta_max         25.04
_diffrn_reflns_theta_min         2.24
_diffrn_standards_decay_%        0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.436
_exptl_absorpt_correction_T_max  0.9025
_exptl_absorpt_correction_T_min  0.6632
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS 2007/2'
_exptl_crystal_colour            COLOURLESS
_exptl_crystal_density_diffrn    1.354
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       NEEDLE
_exptl_crystal_F_000             480
_exptl_crystal_size_max          0.45
_exptl_crystal_size_mid          0.07
_exptl_crystal_size_min          0.04
_refine_diff_density_max         0.488
_refine_diff_density_min         -0.239
_refine_diff_density_rms         0.072
_refine_ls_abs_structure_details
'Flack H D (1983), Acta Cryst. A39, 876-881, 1795 friedel pairs measured.'
_refine_ls_abs_structure_Flack   -0.17(15)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.038
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     286
_refine_ls_number_reflns         3835
_refine_ls_number_restraints     31
_refine_ls_restrained_S_all      1.045
_refine_ls_R_factor_all          0.0982
_refine_ls_R_factor_gt           0.0757
_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^)+(0.0983P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1760
_refine_ls_wR_factor_ref         0.1874
_reflns_number_gt                2856
_reflns_number_total             3835
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            jo101691n_si_005.cif
_cod_data_source_block           ocmucc
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to the built-in table from CIF Core dictionary named
'cif_core.dic' version 2.4.1 from
2010-06-29.

'_exptl_absorpt_correction_type' value 'MULTI-SCAN'
changed to 'multi-scan' according to the built-in table from CIF Core
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1646 2011-03-28 12:23:43Z adriana 
;
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               4025871
_nottingham_internal_coll_name   OCMUCC
_nottingham_internal_coll_number 8975
_nottingham_internal_coll_client MU/CJH
_nottingham_internal_coll_type   SPHERE
_nottingham_internal_coll_frame_time 60s
_nottingham_internal_coll_frame_width '0.3 DEGREES'
_nottingham_internal_coll_frame_method '\w scans'
_nottingham_internal_coll_user   WL
_nottingham_internal_coll_date   29/9/2009
_nottingham_internal_process_user WL
_nottingham_internal_process_date 2/11/2009
_nottingham_internal_solution_user WL
_nottingham_internal_solution_date 2/11/2009
_nottingham_internal_refinement_user WL
_nottingham_internal_refinement_date 2/11/2009
_nottingham_internal_validation_user WL
_nottingham_internal_validation_date 12/03/2010
_nottingham_internal_archive_date 12/3/2010