作者:Susan C. Wilkinson、Oscar Lozano、Marie Schuler、Maria C. Pacheco、Roger Salmon、Véronique Gouverneur
DOI:10.1002/anie.200901795
日期:2009.9.7
A refreshing cascade: General fluorocyclization reactions will breathe new life into the use of fluorinated hetero‐ and carbocycles as pharmaceuticals and agrochemicals. Allyl silanes have now been shown to undergo fluorination–cyclization with NF reagents to give cis‐ and trans‐substituted fluorinated heterocycles selectively (see scheme). The correct choice of silyl group was critical to prevent
Silicon-directed stereoselectivesyn addition of hydroxy group to olefinic double bond occurs intramolecularly in an acid-catalyzed cyclization of vinylsilanes bearing hydroxy group. Thus 5-dimethylphenylsilyl-4-penten-1-ol is smoothly cyclized to 2-(dimethylphenylsilyl)methyltetrahydrofuran upon the treatment of a catalytic amount ofp-toluenesulfonic acid (TsOH) or TiCl4.
Cp<sub>2</sub>TiCl<sub>2</sub>-Catalyzed Regio- and Chemoselective One-Step Synthesis of γ-Substituted Allylsilanes from Terminal Alkenes Using Dianion-Type Zincate (SiSiNOL-Zn-ate)
A regio-/chemoselective silylation reaction of various functionalized terminal alkenes in the presence of titanocene dichloride, based on a newly designed dianion-type zincate, was developed. The present silylation of terminal alkenes is a powerful tool for the one-pot generation of regiocontrolled functionalized allysilanes, which are available for various transformation reactions, such as hydroxyalkylation, epoxidation, and hydroboration.