When 2 + 2 isn't 4

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SELENIUM HETEROCYCLES XXXX [I] SYNTHESES OF 4- (2-PYRAZINYL) - 1, 2, 3: SELENADIAZOLE AND 4- (2-PYRAZILYL)' - l,2,3- THIADIAZOLE

Reaction of thionyl chloride with 2-acetyl-1- benzenesulfonylpyrrole semicarbazone (6 c) gave 4 - (1- benzenesulfonyl-2 - pyrrolyl) - 1, 2, 3 -thiadiazole (lc). Selenium dioxide oxidation of 2-acetylpyrazine semicarbazone (10) in acetic acid afforded 4- (2-pyrazinyl) - 1, 2, 3- selenadiazole (4). Reaction of thionyl chloride with compound 10 gave 4- (2-pyrazinyl) - 1, 2, 3- thiadiazole (3)....

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In the title compound, C(16)H(13)FO(4), the dihedral angle between the benzene rings is 84.28 (8)°. In the crystal, C-H⋯F and C-H⋯O hydrogen bonds link the mol-ecules to form a three-dimensional network. The crystal structure is consolidated by C-H⋯π inter-actions and short F⋯F contacts [2.7748 (14) Å] also occur.

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ژورنال

عنوان ژورنال: Acta Crystallographica Section A Foundations of Crystallography

سال: 2005

ISSN: 0108-7673

DOI: 10.1107/s0108767305080335