Metal free chemoselective reduction of α-keto amides using TBAF as catalyst
作者:N. Chary Mamillapalli、Govindasamy Sekar
DOI:10.1039/c4ra13090a
日期:——
metal and ligand free chemoselective reduction of the keto group and complete reduction of the both keto and amide groups of α-keto amide with hydrosilanes using tetrabutylammoniumflouride (TBAF) as catalyst have been accomplished. This methodology affords an efficient and economic route for the synthesis of biologically important α-hydroxyamides and β-amino alcohols. The other important advantage of
A chemoselective reduction of α‐keto amides to biologically important α‐hydroxy amides (mandelamides) by polymethylhydrosiloxane (PMHS) using 5 mol% potassium phosphate (K3PO4) as catalyst has been developed. This transition metal‐free protocol discloses excellent chemoselectivity for the ketone reduction of α‐keto amides in the presence of other reducible functionalities like ketone, nitro, halides
已开发出使用5 mol%磷酸钾(K 3 PO 4)作为催化剂,通过聚甲基氢硅氧烷(PMHS)将α-酮酰胺化学选择性还原为生物学上重要的α-羟基酰胺(扁桃酰胺)的方法。该无过渡金属方案公开了在存在其他可还原官能团(例如酮,硝基,卤化物,腈和酰胺)的情况下,α-酮酰胺的酮还原反应具有出色的化学选择性。此外,化学选择性还原的α-羟基酰胺已被衍生为无异氰酸酯的Passerini加合物。所述Ñ烷基-α羟基酰胺已经通过用甲磺酰cholride和三乙胺处理被成功地转化为3- phenyloxindole衍生物。
Copper-Catalyzed Synthesis of Azaspirocyclohexadienones from α-Azido-<i>N</i>-arylamides under an Oxygen Atmosphere
作者:Shunsuke Chiba、Line Zhang、Jian-Yuan Lee
DOI:10.1021/ja1027327
日期:2010.6.2
copper-catalyzed reaction of alpha-azido-N-arylamides was found to proceed under an oxygen atmosphere to afford azaspirocyclohexadienones. The present transformation is carried out by a sequence of denitrogenative formation of iminyl copper species from alpha-azido-N-arylamides and their imino-cupration with an intramolecular benzene ring on the amido nitrogen followed by consecutive formation of C=O bonds. The
paper reports on the selective conversion of alkyl azido groups at the carbonyl α-position to diazo compounds. Through β-elimination of dinitrogen, followed by hydrazone formation/decomposition, α-azidocarbonyl moieties were transformed into α-diazo carbonyl groups in one step. As these reaction conditions do not involve aryl or general alkyl azides, site-selective conversions of di- and triazides were
Chemoselective reduction of α-keto amides using nickel catalysts
作者:N. Chary Mamillapalli、Govidasamy Sekar
DOI:10.1039/c4cc02744b
日期:——
Ni-catalysts are used for the first time to synthesize α-hydroxy amides and β-amino alcohols from α-keto amides by chemoselective and complete reduction using hydrosilanes.