ChemInform Abstract: Enantioselective Addition of Allylic Trimethoxysilanes to Aldehydes Catalyzed by p‐Tol‐BINAP×AgF.

Abstract

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Synthesis and Topoisomerase I inhibitory properties of klavuzon derivatives

“…1:8 EtOAc/Hexane) furnished desired asymmetric alcohol. 18). Purification of crude product by column chromatography on silica gel (1:6, EtOAc:Hexane) furnished 167 mg of (R)-1-(4-(dime thylamino)naphthalen-1-yl)but-3-en-1-ol as colorless oil, with 54% yield.…”

“…Asymmetric allylation of the 4-dimethylamino-1naphthaldehyde (17) was performed by allyltrimethoxysilane in the presence of R-Tol-BINAP.AgF complex at À20°C to produce R-homoallylic alcohol 18 with 69% yield [18]. Chiral HPLC studies with two separate chiral columns were performed to determine the ee% of the product and it showed a single peak, which might be the result of formation of a single enantiomer or poor resolution of enantiomers in the columns.…”

“…Next, the formed homoallylic alcohols (18,24,27,30, and 34-36) were subjected to acrylate ester formation with acryloyl chloride. Yields of the esterification reactions were between 73% and 97%, except for compound 18, which was used without purification because of its decomposition in the silica gel column.…”

From designer Lewis acid to designer Brønsted acid towards more reactive and selective acid catalysis

“…25 ), 26 ) Not only main group metal catalysts but also transition metal catalysts having the C-2 symmetric structure can be used for asymmetric synthesis via selective activation of carbonyls. 27 )…”