A facile synthesis of 2‐amino‐1,3‐oxazoles via CuI‐catalyzed oxidative cyclization of enamines and N,N‐dialkyl formamides has been developed. The reaction proceeds through an oxidative C−N bond formation, followed by an intramolecular C(sp2)−H bond functionalization/C−O cyclization in one pot. This protocol provides direct access to useful 2‐amino‐1,3‐oxazoles and features protecting‐group‐free nitrogen
[EN] E-ISOMERIC beta-AROMATIC OR HETEROAROMATIC SUBSTITUTED beta-ACYLAMINO-ACRYLATES AND METHODS OF PREPARING THE SAME<br/>[FR] DOLLAR G(B)-ACYLAMINO-ACRYLATES E-ISOMERES A SUBSTITUTION DOLLAR G(B)-AROMATIQUE OU HETEROAROMATIQUE ET LEUR PROCEDES DE PREPARATION
申请人:DSM IP ASSETS BV
公开号:WO2004011414A1
公开(公告)日:2004-02-05
E-isomeric ß-(hetero) aromatically substituted acylaminoacrylates are of great economic interest since with them, by means of hydration, precursors of appropriately substituted (ß-amino acids can be prepared and, by doing so, lead to higher enantio-selectivities than the corresponding Z-isomers. The invention describes novel E-isomeric R-aromatically or ß-heteroaromatically substituted ß-acylaminoacrylates of the general formula (I): in which R represents hydrogen or a substituted or unsubstituted alkyl or aromatic or heteroaromatic residue, and R' represents a substituted or unsubstituted aromatic or heteroaromatic residue, R' represents H, a substituted or unsubstituted alkyl or aromatic or heteroaromatic residue, and R'' represents H, a substituted or unsubstituted alkyl, acyl, aromatic or heteroaromatic residue. According to the invention, the compounds according to the general formula (I) are prepared by acylation at temperatures below the boiling point of the reaction mixture.
complexes were highly efficient catalysts for asymmetrichydrogenation of β-aryl-substituted β-(acylamino)acrylates and β-aryl-substituted β-keto esters. The Ru-bisphosphinite catalysts can tolerate an E/Z mixture of β-aryl-substituted β-(acylamino)acrylates. These highly enantioselective hydrogenations provide a useful way to prepare β-aryl-substituted β-amino acids and β-hydroxyl acids.
Synthesis of trifluoromethylated 2<i>H</i>-azirines through Togni reagent-mediated trifluoromethylation followed by PhIO-mediated azirination
作者:Jiyun Sun、Xiaohua Zhen、Huaibin Ge、Guangtao Zhang、Xuechan An、Yunfei Du
DOI:10.3762/bjoc.14.123
日期:——
The reaction of enamine compounds with the Togni reagent in the presence of CuI afforded β-trifluoromethylated enamine intermediates, which were converted directly to biologically interesting trifluoromethylated 2H-azirines by an iodosobenzene (PhIO)-mediated intramolecular azirination in a one-pot process.
Hypervalent Iodine(III)-Mediated Benzannulation of Enamines with Alkynes: an Efficient Synthesis of Substituted Aminonaphthoic Acid Derivatives
作者:Peng Gao、Mingjin Fan、Zijing Bai、Yunyang Wei
DOI:10.1002/cjoc.201400802
日期:2015.4
the synthesis of useful substituted 1‐amino‐2‐naphthoic acid derivatives via benzannulationreactions. Various N‐unsubstituted and N‐alkyl substituted aromatic enamines with terminal alkynes and non‐terminal alkynes can be converted into corresponding 1‐amino‐2‐naphthoic acid derivatives under mild reaction conditions. When meta‐substituted phenyl enamines were employed in the reaction, two cyclization