A novel intramolecular homoenolate annulation leading to the formation of cyclopentene-fused macrocycles.
Seetha Lakshmi, K. C.; Sinu, C. R.; Padmaja, D. V. M.; Gopinathan, Anilkumar; Suresh, Eringathodi; Nair, Vijay; Organic letters 16 (2014) 5532–5535; doi:10.1021/ol5023239

data_1518072
_publ_section_title
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 A novel intramolecular homoenolate annulation leading to the formation of
 cyclopentene-fused macrocycles.
;
_journal_issue                   21
_journal_name_full               'Organic letters'
_journal_page_first              5532
_journal_page_last               5535
_journal_paper_doi               10.1021/ol5023239
_journal_volume                  16
_journal_year                    2014
_chemical_formula_sum            'C26 H24 O2'
_chemical_formula_weight         368.45
_space_group_IT_number           14
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_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
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_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 100.3850(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   12.3878(11)
_cell_length_b                   9.8635(9)
_cell_length_c                   16.2960(14)
_cell_measurement_reflns_used    5882
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      28.04
_cell_measurement_theta_min      2.27
_cell_volume                     1958.5(3)
_computing_cell_refinement       'BRUKER SMART'
_computing_data_collection       'BRUKER SMART'
_computing_data_reduction        'BRUKER SAINT'
_computing_molecular_graphics    ORTEP
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      150(2)
_diffrn_measured_fraction_theta_full 0.951
_diffrn_measured_fraction_theta_max 0.951
_diffrn_measurement_device_type  'BRUKER SMART APEX CCD DIFFRACTOMETER'
_diffrn_measurement_method       'OMEGA-PHI SCAN'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0246
_diffrn_reflns_av_sigmaI/netI    0.0275
_diffrn_reflns_limit_h_max       16
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            11281
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_diffrn_reflns_theta_max         27.99
_diffrn_reflns_theta_min         1.67
_exptl_absorpt_coefficient_mu    0.077
_exptl_absorpt_correction_T_max  0.9862
_exptl_absorpt_correction_T_min  0.9675
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'BRUKER SADABS'
_exptl_crystal_colour            COLOURLESS
_exptl_crystal_density_diffrn    1.250
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       BLOCKS
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_exptl_crystal_size_mid          0.32
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_refine_ls_extinction_method     none
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_refine_ls_matrix_type           full
_refine_ls_number_parameters     337
_refine_ls_number_reflns         4489
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.036
_refine_ls_R_factor_all          0.0557
_refine_ls_R_factor_gt           0.0494
_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^)+(0.0787P)^2^+0.4852P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1343
_refine_ls_wR_factor_ref         0.1404
_reflns_number_gt                3861
_reflns_number_total             4489
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol5023239_si_002.cif
_cod_data_source_block           391slm
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'MONOCLINIC' changed to 'monoclinic'
according to
/home/saulius/struct/COD-crude-data--automatic-downloads/rss-feeds/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from
2011-04-26.

'_exptl_absorpt_correction_type' value 'MULTI-SCAN'
changed to 'multi-scan' according to
/home/saulius/struct/COD-crude-data--automatic-downloads/rss-feeds/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 2827 2014-09-09 07:05:25Z andrius 

 Adding full bibliography for 1518072.cif.
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_cod_original_sg_symbol_H-M      P21/c
_cod_database_code               1518072