Unexpected beauty and diversity in the structures of three homologous 4,5-dialkoxy-1-ethynyl-2-nitrobenzenes: the subtle interplay between intermolecular C-H...O hydrogen bonds and alkyl chain length.
Oburn, Shalisa M.; Bosch, Eric; Acta crystallographica. Section C, Structural chemistry 73 (2017) 814–819; doi:10.1107/S2053229617012761

data_2311913
_publ_section_title
;
 Unexpected beauty and diversity in the structures of three homologous
 4,5-dialkoxy-1-ethynyl-2-nitrobenzenes: the subtle interplay between
 intermolecular C-H...O hydrogen bonds and alkyl chain length.
;
_journal_issue                   'Pt 10'
_journal_name_full
'Acta crystallographica. Section C, Structural chemistry'
_journal_page_first              814
_journal_page_last               819
_journal_paper_doi               10.1107/S2053229617012761
_journal_volume                  73
_journal_year                    2017
_chemical_formula_moiety         'C18 H25 N O4'
_chemical_formula_sum            'C18 H25 N O4'
_chemical_formula_weight         319.39
_chemical_name_common
;
1-ethynyl-2-nitro-4,5-bis-pentoxybenzene
;
_space_group_crystal_system      triclinic
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_atom_sites_solution_hydrogens   mixed
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_diffrn_ambient_temperature      100(2)
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_diffrn_measurement_device_type  'Bruker APEXII CCD area-detector'
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_diffrn_radiation_monochromator  graphite
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_exptl_absorpt_correction_T_max  0.7455
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_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
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'w = 1/[\s^2^(Fo^2^)+(0.1254P)^2^+0.8636P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
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_refine_ls_wR_factor_ref         0.2621
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_reflns_threshold_expression     I>2\s(I)
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