Vilsmeier-Haack Reagents. Novel Electrophiles for the One-Step Formylation of<i>O</i>-Silylated Ethers to<i>O</i>-Formates
作者:Jean-Paul Lellouche、Vadim Kotlyar
DOI:10.1055/s-2004-815435
日期:——
Various O-silylated substrates were effectively converted in one-step to their corresponding O-formates using electrophilic racemic and homochiral Vilsmeier-Haack reagents. Reactivity trends of these transformations were examined that, specifically, emphasized their synthetic potential.
Preparation of formate esters from O-TBDMS/O-TES protected alcohols. A one-step conversion using the Vilsmeier-Haack complex
作者:Sylvain Koeller、Jean-Paul Lellouche
DOI:10.1016/s0040-4039(99)01453-7
日期:1999.9
O-tert-Butyldimethylsilylated (O-TBDMS) or O-triethylsilylated (O-TES) alcohols were converted in one step to their corresponding formates under Vilsmeier-Haack conditions (). The scope and limitations of this novel reaction for interconverting alcohol protecting groups are described.
primary and secondary alcohols and phenols can be converted efficiently to their corresponding TBDMS ethers using TBDMCS/imidazole undersolvent-freeconditions. Elimination of DMF, accompanied with an easy non-aqueous work-up and a high rate enhancement of the reaction are worthy to be mentioned for the presented method. The reactions show absolute chemoselectivity for the protection of primary in the
Preparation and regio- and diastereoselective reactions of allylic zirconium reagents from allylic ether derivatives
作者:Hisanaka Ito、Takeo Taguchi、Yuji Hanzawa
DOI:10.1016/s0040-4039(00)91605-8
日期:1992.3
Allylic zirconium reagents were generated by treating allylic ether derivatives with zirconocene “Cp2Zr”. The allylic zirconium reagents reacted with aldehydes in highly regio- and diastereoselective manner to give homoallylicalcohol compounds.
New Method for Oxidative Carbon-carbon Bond Formation by the Reaction of Allyl Ethers, 2,3-Dichloro-5,6-dicyano-<i>p</i>-benzoquinone(DDQ) and Silyl Carbon Nucleophiles
作者:Yujiro Hayashi、Teruaki Mukaiyama
DOI:10.1246/cl.1987.1811
日期:1987.9.5
Allylethers are oxidized by DDQ to generate the corresponding cationic species, which in turn react with silyl carbon nucleophiles in the presence of a catalytic amount of lithium perchlorate to afford the coupled products in a one-pot procedure in good yields.