Synthesis of ultrahighly electron-deficient pyrrolo[3,4-d]pyridazine-5,7-dione by inverse electron demand Diels-Alder reaction and its application as electrochromic materials.
Ye, Qun; Neo, Wei Teng; Cho, Ching Mui; Yang, Shuo Wang; Lin, Tingting; Zhou, Hui; Yan, Hong; Lu, Xuehong; Chi, Chunyan; Xu, Jianwei; Organic letters 16 (2014) 6386–6389; doi:10.1021/ol503178m

data_1518392
_publ_section_title
;
 Synthesis of ultrahighly electron-deficient
 pyrrolo[3,4-d]pyridazine-5,7-dione by inverse electron demand Diels-Alder
 reaction and its application as electrochromic materials.
;
_journal_issue                   24
_journal_name_full               'Organic letters'
_journal_page_first              6386
_journal_page_last               6389
_journal_paper_doi               10.1021/ol503178m
_journal_volume                  16
_journal_year                    2014
_chemical_formula_moiety         'C20 H17 Br2 N3 O4'
_chemical_formula_sum            'C20 H17 Br2 N3 O4'
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'SHELXTL, Acta Cryst., Sect. A 2008, 64, 112-122.'
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_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'Bruker AXS D8 Venture '
_diffrn_measurement_method       'profile data from \q/2\q scans'
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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^)+(0.0442P)^2^+0.7122P] where P=(Fo^2^+2Fc^2^)/3'
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_reflns_threshold_expression     'I > 2\s(I)'
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_cod_depositor_comments
'Adding full bibliography for 1518392--1518393.cif.'
_cod_database_code               1518392
_shelx_estimated_absorpt_t_min   0.566
_shelx_estimated_absorpt_t_max   0.686
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_shelx_hkl_checksum              26151