Three tetramethylketals of 2,5-distyryl-[1,4]benzoquinones
Irngartinger, H.; Lichenthäler, J.; Acta Crystallographica Section C 50 (1994) 1154–1156; doi:10.1107/S0108270193011503

data_2009905
_publ_section_title
;
 Three tetramethylketals of 2,5-distyryl-[1,4]benzoquinones
;
_journal_issue                   7
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              1154
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_journal_paper_doi               10.1107/S0108270193011503
_journal_volume                  50
_journal_year                    1994
_chemical_formula_sum            'C28 H32 O4'
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_cod_depositor_comments
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The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value '1/[\s(F~o~)^2^]' was changed to
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Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 

The authors quote the space group as P 21/n but this yields and chemically
unreasonable polymeric structure, putting it as P 21/c generates the monomeric
species described in the original paper. Hence, we think that the group is
indeed P 21/c

miguel
;
_cod_original_cell_volume        1215.2(8)
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               2009905