Nucleophilic Attack on 4,5-Dihydro-4-alkyl-3H-dinaphtho[2,1-c:1',2'-e]thiepinium Salts. A Convenient Approach to New 2,2'-Bidentate 1,1'-Binaphthalene Ligands with Sulfur Donor Atoms

Autor:	Irena G. Stará, Ivo Stary, Jiří Závada, M. Tichy, Pavel Fiedler
Rok vydání:	1994
Předmět:	chemistry.chemical_classification Perchlorate chemistry.chemical_compound Denticity Tetrafluoroborate Nucleophile Bicyclic molecule Chemistry Organic Chemistry Iodide Absolute configuration Counterion Medicinal chemistry
Zdroj:	The Journal of Organic Chemistry. 59:1326-1332
ISSN:	1520-6904 0022-3263
Popis:	The title dihydrothiepinium salts (6) react with a wide range of N-, S-, Se-, O-, and C-nucleophiles to afford dihydrothiepin (5) and/or the corresponding bidentate ligands (7). The dual course of the reaction can be controlled by a judicious choice of the substrate counterion. In most instances, an iodide counterion aids formation of dihydrothiepins (5), whereas perchlorate, tetraphenyl borate, or tetrafluoroborate coun- terions favor formation of bidentate ligands (7). An explanation based on a competition between the counterion and the external nucleophile is provided. Dihydrothiepinium salts (6) are easily accessible from dibro- mide (R,S)-(4) via dihydrothiepin (R,S)-5. Individual enantiomers (R)- and (S)-(5) have been obtained by resolution on a preparative triace- tylcellulose (TAC) column ans assigned absolute configuration on the basis of CD spectra and chemical correlation
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::951bbfd5dd7f21e145461f5040a59f7d https://doi.org/10.1021/jo00085a021 Zobrazit plný text záznamu