Amine-boranes as Dual-Purpose Reagents for Direct Amidation of Carboxylic Acids
作者:P. Veeraraghavan Ramachandran、Henry J. Hamann、Shivani Choudhary
DOI:10.1021/acs.orglett.0c03184
日期:2020.11.6
Amine-boranes serve as dual-purpose reagents for direct amidation, activating aliphatic and aromatic carboxylicacids and, subsequently, delivering amines to provide the corresponding amides in up to 99% yields. Delivery of gaseous or low-boiling amines as their borane complexes provides a major advantage over existing methodologies. Utilizing amine-boranes containing borane incompatible functionalities
The cycloaddition of N-chlorosulfonyl-isocyanate with isoprene, butadiene and a polyolefin as well as the reaction of ketenes with some bis-azomethines were investigated. Suitably substituted bis-azomethines could be separated in the rac. and the meso-form. The reactivity of the azetidinones towards hydrolysis and hydrogenation was tested. Attempts to polymerise 4-vinyl-azetidin-2-one, polyazetidinone
A single-component, air-stable nickel precatalyst can catalyze the isomerization of allylamides for the synthesis of enamides. The scope of the reaction encompasses various substituted allylamides and allylcarbamates as well as homoallylamides. The reaction can be performed on a multigram-scale without specialized glove-box equipment or Schlenk techniques.
intramolecular [2+2] cycloadditionreaction of acyl ketenes formed from metastable mesoionic 1,3-oxazinium-4-olates was investigated by experimental and theoretical methods. The ring opening of the mesoionic N -allyl-2-(2-arylvinyl)-1,3-oxazinium-4-olates led to the formation of unstable acyl ketenes. Although there are four possible paths for an intramolecular [2+2] cycloaddition reaction involving the
Ruthenium(<scp>ii</scp>)-catalyzed C–H activation and (4+2) annulation of aromatic hydroxamic acid esters with allylic amides
作者:Chandan Kumar Giri、Suman Dana、Mahiuddin Baidya
DOI:10.1039/d1cc04422b
日期:——
using aromatic hydroxamicacid esters as the oxidizing directing group and allylic amides as unactivated olefin coupling partners, delivering a wide variety of aminomethyl isoquinolinones in good to excellent yields. This annulation is distinctive as allylic congeners typically result in allylation and not the annulation. Late-stage derivatization of a bioactive synthetic bile acid has been showcased
据报道,在 Ru( II ) 催化下的 (4+2) 环化使用芳族异羟肟酸酯作为氧化导向基团,烯丙基酰胺作为未活化的烯烃偶联伙伴,以良好到优异的产率提供各种氨甲基异喹啉酮。这种环化是独特的,因为烯丙基同类物通常导致烯丙基化而不是环化。已经展示了生物活性合成胆汁酸的后期衍生化。