Fluorinated 1,3λ4δ2,2,4-benzodithiadiazines - A synthetic, structural and theoretical study

Fluorinated 1,3λ4δ2,2,4-benzodithiadiazines - A synthetic, structural and theoretical study Научная публикация

Журнал

European Journal of Inorganic Chemistry
ISSN: 1434-1948 , E-ISSN: 1099-0682

Вых. Данные

Год: 2003, Номер: 1, Страницы: 77-88 Страниц : 12 DOI: 10.1002/ejic.200390016

Ключевые слова

Antiaromaticity; Electrophilic cyclisation; Fluorinated 1,3λ4δ2,2,4-benzodithiadiazines; Molecular structure; NICS; Nucleophilic cyclisation

Авторы

Makarov A.Yu. ¹ , Bagryanskaya I.Yu. ¹ , Blockhuys F. ² , Van Alsenoy C. ² , Gatilov Y.V. ¹ , Knyazev V.V. ¹ , Maksimov A.M. ¹ , Mikhalina T.V. ¹ , Platonov V.E. ¹ , Shakirov M.M. ¹ , Zibarev A.V. ¹

Организации

1	Institute of Organic Chemistry, Russian Academy of Sciences, 630090 Novosibirsk, Russian Federation
2	Department of Chemistry, University of Antwerp (UIA), Universiteitsplein 1, 2610 Wilrijk (Antwerpen), Belgium

The series of title compounds has been prepared through both electrophilic (C6HnF5-n-N=S=N-SiMe3 + SCl2) and nucleophilic (C6HF4_S-N=S=N-SiMe3 + CsF) intramolecular ortho-cyclisation reactions, and the former route seems to be the more effective. High regioselectivity of the ring-closing procedures is observed in both cases. The compounds were characterised by X-ray crystallography and multinuclear (1H, 13C, 15N and 19F) NMR spectroscopy. In accordance with GIAO calculations, 15N{1H} experiments and the effects observed on complete substitution of hydrogen by fluorine, the high-field signal in the 15N NMR spectra can be assigned to N-4 and the low-field signal to N-2. In the crystal, 5,6,7-trifluoro-(5) and 5,6,8-trifluoro-1,3λ4δ22,4- benzodithiadiazine (6) are planar, whereas the 6,8-difluoro derivative 3 is bent along the S1⋯N4 line by 8.3°. According to NICS calculations the heterocycle moiety in this compound class is antiaromatic while the carbocycle is aromatic. The fluorine substituents increase the aromaticity - and in some cases (especially when a fluorine atom is present in the 8-position) the antiaromaticity - of the corresponding rings. The ortho-fluoro-containing starting material C6HnF5-n-N=S=N-SiMe3 (n = 2: 10) cyclises to the fluorinated 2,1,3-benzothiadiazole 27 upon treatment with CsF instead of SCl2. For starting compound 6-HC6F4-S-N=S=N-SiMe3 (14) the planar (Z,E) configuration features a short intramolecular H⋯N contact, as evidenced by X-ray diffraction. Both the reaction pathways mentioned are also discussed. © Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2003.

Makarov A.Y. , Bagryanskaya I.Y. , Blockhuys F. , Van A.C. , Gatilov Y.V. , Knyazev V.V. , Maksimov A.M. , Mikhalina T.V. , Platonov V.E. , Shakirov M.M. , Zibarev A.V.
Fluorinated 1,3λ4δ2,2,4-benzodithiadiazines - A synthetic, structural and theoretical study
European Journal of Inorganic Chemistry. 2003. N1. P.77-88. DOI: 10.1002/ejic.200390016 WOS Scopus РИНЦ

Опубликована в печати:

1 янв. 2003 г.

Web of science	WOS:000180388900013
Scopus	2-s2.0-0037238715
РИНЦ	13440920
OpenAlex	W2036043467