Ring expansion/homologation–aldehyde condensation cascade using tert-trihalomethylcarbinols.
Falck, J. R.; He, Anyu; Reddy, L. Manmohan; Kundu, Abhijit; Barma, Deb K.; Bandyopadhyay, A.; Kamila, Sukanta; Akella, Radha; Bejot, Romain; Mioskowski, Charles; Organic letters 8 (2006) 4645–4647; doi:10.1021/ol061953q

data_1506233
_publ_section_title
;
 Ring expansion/homologation--aldehyde condensation cascade using
 tert-trihalomethylcarbinols.
;
_journal_issue                   20
_journal_name_full               'Organic letters'
_journal_page_first              4645
_journal_page_last               4647
_journal_paper_doi               10.1021/ol061953q
_journal_volume                  8
_journal_year                    2006
_chemical_formula_sum            'C20 H20 O'
_chemical_formula_weight         276.37
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yab'
_symmetry_space_group_name_H-M   'P 1 21/a 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.000(5)
_cell_angle_beta                 99.693(5)
_cell_angle_gamma                90.000(5)
_cell_formula_units_Z            4
_cell_length_a                   6.193(5)
_cell_length_b                   17.433(5)
_cell_length_c                   14.493(5)
_cell_measurement_temperature    291(2)
_cell_volume                     1542.4(14)
_computing_cell_refinement       'HKL2000 v095.373'
_computing_data_collection       'collect, Nonius 1999'
_computing_data_reduction        'HKL2000 v095.373'
_computing_publication_material  'XCIF (Sheldrick and Bruker 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      291(2)
_diffrn_measured_fraction_theta_full 0.964
_diffrn_measured_fraction_theta_max 0.964
_diffrn_measurement_device_type  'Kappa CCD'
_diffrn_measurement_method       collect
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_R_equivalents  0.0000
_diffrn_reflns_av_sigmaI/netI    0.1533
_diffrn_reflns_limit_h_max       5
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            1615
_diffrn_reflns_theta_full        20.80
_diffrn_reflns_theta_max         20.80
_diffrn_reflns_theta_min         2.74
_exptl_absorpt_coefficient_mu    0.071
_exptl_absorpt_correction_type   none
_exptl_absorpt_process_details   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.194
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needles
_exptl_crystal_F_000             592
_exptl_crystal_size_max          0.12
_exptl_crystal_size_mid          0.04
_exptl_crystal_size_min          0.02
_refine_diff_density_max         0.208
_refine_diff_density_min         -0.213
_refine_diff_density_rms         0.051
_refine_ls_extinction_coef       0.34(8)
_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   1.006
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     196
_refine_ls_number_reflns         1497
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.006
_refine_ls_R_factor_all          0.1797
_refine_ls_R_factor_gt           0.0961
_refine_ls_shift/su_max          0.005
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1999P)^2^+0.7634P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2076
_refine_ls_wR_factor_ref         0.1727
_reflns_number_gt                808
_reflns_number_total             1615
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol061953qsi20060807_045002.cif
_cod_data_source_block           shelxl_26
_cod_original_sg_symbol_H-M      'p 21/a'
_cod_database_code               1506233