Divergence in the reactivity between amine- and phosphine-catalyzed cycloaddition reactions of allenoates with enynals: one-pot gold-catalyzed synthesis of trisubstituted benzofurans from the [3 + 2] cycloadduct via 1,2-alkyl migration and dehydrogenation.
Kumari, A. Leela Siva; Swamy, K. C. Kumara; The Journal of organic chemistry 80 (2015) 4084–4096; doi:10.1021/acs.joc.5b00415

data_4036180
_publ_section_title
;
 Divergence in the reactivity between amine- and phosphine-catalyzed
 cycloaddition reactions of allenoates with enynals: one-pot
 gold-catalyzed synthesis of trisubstituted benzofurans from the [3 + 2]
 cycloadduct via 1,2-alkyl migration and dehydrogenation.
;
_journal_issue                   8
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              4084
_journal_page_last               4096
_journal_paper_doi               10.1021/acs.joc.5b00415
_journal_volume                  80
_journal_year                    2015
_chemical_formula_sum            'C23 H18 O3'
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_space_group_name_Hall           'P 2c -2ac'
_space_group_name_H-M_alt        'P c a 21'
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_symmetry_space_group_name_H-M   'P c a 21'
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_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   12.3414(4)
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_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      70.5600
_cell_measurement_theta_min      4.1620
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_computing_cell_refinement       'CrysAlisPro, Oxford Diffraction Ltd.'
_computing_data_collection       'CrysAlisPro, Oxford Diffraction Ltd.'
_computing_data_reduction        'CrysAlisPro, Oxford Diffraction Ltd.'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Xcalibur, Eos, Gemini'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0146
_diffrn_reflns_av_sigmaI/netI    0.0173
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -9
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_diffrn_reflns_limit_k_min       -24
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       -5
_diffrn_reflns_number            3533
_diffrn_reflns_theta_full        67.07
_diffrn_reflns_theta_max         67.07
_diffrn_reflns_theta_min         4.16
_diffrn_standards_decay_%        none
_diffrn_standards_interval_count 'not applicable'
_diffrn_standards_interval_time  'not applicable'
_diffrn_standards_number         'not applicable'
_exptl_absorpt_coefficient_mu    0.669
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.88299
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'CrysAlisPro, Oxford Diffraction Ltd.'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.272
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needles
_exptl_crystal_F_000             720
_exptl_crystal_size_max          0.28
_exptl_crystal_size_mid          0.18
_exptl_crystal_size_min          0.14
_refine_diff_density_max         0.113
_refine_diff_density_min         -0.207
_refine_diff_density_rms         0.045
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.4(3)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.075
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     236
_refine_ls_number_reflns         2117
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.075
_refine_ls_R_factor_all          0.0483
_refine_ls_R_factor_gt           0.0411
_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^)+(0.0594P)^2^+0.0336P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0988
_refine_ls_wR_factor_ref         0.1049
_reflns_number_gt                1819
_reflns_number_total             2117
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo5b00415_si_002.cif
_cod_data_source_block           compd-16aa
_cod_original_cell_volume        1788.32(10)
_cod_database_code               4036180