Michael, Michael-aldol and Michael-Michael reactions of enolate equivalents of butane-2,3-diacetal protected glycolic acid derivatives.
Ley, Steven V.; Dixon, Darren J.; Guy, Richard T.; Rodríguez, Félix; Sheppard, Tom D.; Organic & biomolecular chemistry 3 (2005) 4095–4107; doi:10.1039/b512410g

data_7150300
_publ_section_title
;
 Michael, Michael-aldol and Michael-Michael reactions of enolate
 equivalents of butane-2,3-diacetal protected glycolic acid
 derivatives.
;
_journal_issue                   22
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              4095
_journal_page_last               4107
_journal_paper_doi               10.1039/b512410g
_journal_volume                  3
_journal_year                    2005
_chemical_formula_moiety         'C20 H34 O7'
_chemical_formula_sum            'C20 H34 O7'
_chemical_formula_weight         386.47
_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                   9.2857(3)
_cell_length_b                   10.4352(3)
_cell_length_c                   21.1270(8)
_cell_measurement_reflns_used    41035
_cell_measurement_temperature    180(2)
_cell_measurement_theta_max      27.48
_cell_measurement_theta_min      1.00
_cell_volume                     2047.17(12)
_computing_cell_refinement       'HKL Scalepack (Otwinowski & Minor 1997)'
_computing_data_collection       'Collect (Nonius B.V. 1998)'
_computing_data_reduction
;
HKL Denzo and Scalepack (Otwinowski & Minor 1997)
;
_computing_publication_material  'SHELXL-97 (Sheldrick 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick 1997)'
_computing_structure_solution    'SIR-92 (Altomare et al. 1994)'
_diffrn_ambient_temperature      180(2)
_diffrn_measured_fraction_theta_full 0.989
_diffrn_measured_fraction_theta_max 0.989
_diffrn_measurement_device_type  'Nonius Kappa CCD'
_diffrn_measurement_method       'Thin slice \w and \f scans'
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0861
_diffrn_reflns_av_sigmaI/netI    0.0596
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       27
_diffrn_reflns_limit_l_min       -25
_diffrn_reflns_number            12532
_diffrn_reflns_theta_full        27.38
_diffrn_reflns_theta_max         27.38
_diffrn_reflns_theta_min         4.02
_exptl_absorpt_coefficient_mu    0.094
_exptl_absorpt_correction_T_max  1.001
_exptl_absorpt_correction_T_min  0.776
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
multi-scan from symmetry-related measurements
Sortav (Blessing 1995)
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.254
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             840
_exptl_crystal_size_max          0.32
_exptl_crystal_size_mid          0.23
_exptl_crystal_size_min          0.18
_refine_diff_density_max         0.644
_refine_diff_density_min         -0.446
_refine_diff_density_rms         0.077
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   1(2)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.055
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     251
_refine_ls_number_reflns         2621
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.055
_refine_ls_R_factor_all          0.0955
_refine_ls_R_factor_gt           0.0685
_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^)+(0.1371P)^2^+0.2194P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1884
_refine_ls_wR_factor_ref         0.2063
_reflns_number_gt                1949
_reflns_number_total             2621
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b512410g.txt
_cod_data_source_block           sl0438
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Orthorhombic' changed to 'orthorhombic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 
;
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               7150300