Studies of Azetidin-2-one as a Reactive Enolate Synthon of β-Alanine for Condensations with Aldehydes and Ketones.
Williams, David R.; Donnell, Andrew F.; Kammler, David C.; Ward, Sarah A.; Taylor, 4th, Levin; The Journal of organic chemistry 81 (2016) 10463–10475; doi:10.1021/acs.joc.6b01585

data_4037139
_publ_section_title
;
 Studies of Azetidin-2-one as a Reactive Enolate Synthon of \b-Alanine for
 Condensations with Aldehydes and Ketones.
;
_journal_issue                   21
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              10463
_journal_page_last               10475
_journal_paper_doi               10.1021/acs.joc.6b01585
_journal_volume                  81
_journal_year                    2016
_chemical_absolute_configuration unk
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_computing_cell_refinement       'SAINT (Bruker, 1999)'
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_computing_molecular_graphics    'SHELXTL (Bruker, 2015)'
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_diffrn_measurement_method       '\w scans'
_diffrn_radiation_type           MoK\a
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_diffrn_reflns_limit_l_min       -20
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_diffrn_source                   'fine-focus sealed tube'
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_exptl_absorpt_correction_type   multi-scan
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_refine_ls_abs_structure_details
;
 Classical Flack method preferred over Parsons because s.u. lower.
;
_refine_ls_abs_structure_Flack   -1.9(6)
_refine_ls_extinction_method     none
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_refine_ls_R_factor_all          0.3227
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_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0380P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2236
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_reflns_Friedel_fraction_max     0.917
_reflns_number_gt                1714
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_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            jo6b01585_si_002.cif
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_cod_original_cell_volume        1604.1(12)
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               4037139
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_min   0.931
_shelx_estimated_absorpt_t_max   0.997
_shelx_res_checksum              70845
_shelx_hkl_checksum              6743