Es werden einige Vertreter von N2‐unsubstituierten N1‐Hydroxyform‐ 2, acet‐ 3 und benzamidinen 4 beschrieben. 3 und 4 geben bei der Umsetzung mit Isocyanaten nur offenkettige O‐Carbamoylierungsprodukte 5und 6. Beim Behandeln mit 1,1′‐Carbonyldiimidazol (CDI) entstehen cyclische Carbonylierungsprodukte 8 und 9 nur in den Acet‐ und Benzamidin‐Reihen. N2‐Substituierte Formamidin‐Derivate 13 geben mit
driven C–H ketoalkylation of glycine derivatives and peptides with cycloalkyl hydroperoxides is presented. This protocol provides a straightforward route to unnatural amino acids bearing a distal carbonyl group with moderate to good yields. Preliminary mechanistic studies revealed that both a SET event and radical chain propagation were involved in this transformation.
The Pd-catalyzed cross-coupling ethoxycarbonylation of aryl boronic acids with N-aryl-α-iminoesters affords aryl carboxylic esters via carbonyl-imino Ï bond cleavage. This unprecedented mode of reaction allows regioselective installation of the ethoxycarbonyl group into target molecules. Mechanism studies have revealed that an unusual 1,2-aryl shift process is involved in the transformation.
Copper-Catalyzed Oxidative [4 + 2]-Cyclization Reaction of Glycine Esters with Anthranils: Access to 3,4-Dihydroquinazolines
作者:Jie Ren、Chao Pi、Yangjie Wu、Xiuling Cui
DOI:10.1021/acs.orglett.9b01246
日期:2019.6.7
synthesis of 3,4-dihydroquinazolines has been developed via copper-catalyzed oxidative cross-dehydrogenative [4 + 2]-cyclization of glycine derivatives with anthranils. This strategy features high efficiency and wide substrate tolerance under simple reaction conditions. Various 3,4-dihydroquinazoline derivatives could be easily obtained starting from titled products through chemical transformations, which
Synthesis of α-(3-Indolyl)glycine Derivatives via Spontaneous Friedel-Crafts Reaction between Indoles and Glyoxylate Imines
作者:Biao Jiang、Zuo-Gang Huang
DOI:10.1055/s-2005-869978
日期:——
Mannich-type Friedel-Crafts reaction between indoles and ethyl glyoxylate imines proceeded spontaneously in the absence of an acid catalyst. Ethyl alpha-(3-indolyl)glycinates were obtained in moderate to high yields. Reaction with (R)-alpha-methylbenzylamine derived imine afforded chiral alpha-(3-indolyl)glycinates with good diastereoselectivities (up to 96:4).