Dimethyl and diethyl esters of 5,6-bis(pyridin-2-yl)pyrazine-2,3-dicarboxylic acid: a comparison
Alfonso, Montserrat; Stoeckli-Evans, Helen; Acta Crystallographica Section E 72 (2016) 233–237; doi:10.1107/S2056989016001080

data_2241522
_publ_section_title
;
 Dimethyl and diethyl esters of
 5,6-bis(pyridin-2-yl)pyrazine-2,3-dicarboxylic acid: a comparison
;
_journal_issue                   2
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              233
_journal_page_last               237
_journal_paper_doi               10.1107/S2056989016001080
_journal_volume                  72
_journal_year                    2016
_chemical_formula_iupac          'C20 H18 N4 O4'
_chemical_formula_moiety         'C20 H18 N4 O4'
_chemical_formula_sum            'C20 H18 N4 O4'
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_chemical_name_systematic
;
Diethyl 5,6-bis(pyridin-2-yl)pyrazine-2,3-dicarboxylate
;
_space_group_crystal_system      tetragonal
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;
<i>CELL</i> in <i>IPDS-I</i> (Stoe & Cie, 2004)
;
_computing_data_collection
;
<i>EXPOSE</i> in <i>IPDS-I</i> (Stoe & Cie, 2004)
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<i>INTEGRATE</i> in <i>IPDS-I</i> (Stoe & Cie, 2004)
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PLATON  (Spek, 2009) and Mercury (Macrae <i>et al.</i>,  2008)
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SHELXL2014 (Sheldrick, 2015), PLATON (Spek, 2009) and
publCIF (Westrip, 2010)
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SHELXL2014 (Sheldrick, 2015)
;
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SHELXS97 (Sheldrick, 2008)
;
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;
SHELXL2014 (Sheldrick, 2015)
;
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'w=1/[\s^2^(Fo^2^)+(0.0925P)^2^] where P=(Fo^2^+2Fc^2^)/3'
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_cod_database_code               2241522
_cod_database_fobs_code          2241522
_shelx_estimated_absorpt_t_min   0.941
_shelx_estimated_absorpt_t_max   0.954
_shelx_hkl_checksum              93538
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