ChemInform Abstract: Effects of the Temperature and Substituents in Chiral TiIV(Salen) Catalysts on the Enantioselectivity of the Addition of Me3SiCN to PhCHO

Autor:	Vitali I. Tararov, Nikolai S. Ikonnikov, Lidia V. Yashkina, Michael North, Vladimir Larichev, Yu. N. Belokon, C. Orizu, Margarita A. Moscalenko
Rok vydání:	2010
Předmět:	Steric effects Addition reaction Chemistry Condensation Organic chemistry General Medicine Enantiomer Medicinal chemistry Catalysis
Zdroj:	ChemInform. 30
ISSN:	1522-2667 0931-7597
Popis:	The enantiomeric purity (ee) of the addition product of Me3SiCN to PhCHO at ∼20 °C catalyzed by chiral TiIV complexes, which were preparedin situ from Ti(OPri)4 and the Schiff bases (condensation products of substituted salicylaldehydes with (1R, 2R)-1,2-diaminocyclohexane), was, on the average, 20–30% lower than that achieved at −80 °C. The substituents at position 5 of 3-tert-butylsalicylaldehyde exert only the steric effect. It was shown that the stereochemical result of the reaction is controlled by the stage which involves the formation of the C−C bond rather than the transfer of the Me3Si group.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::6ea8c212fc1e540f1c4a6e4528419eb8 https://doi.org/10.1002/chin.199952034 Zobrazit plný text záznamu Plný text