Preparation of amides mediated by isopropylmagnesium chloride under continuous flow conditions
作者:Juan de M. Muñoz、Jesús Alcázar、Antonio de la Hoz、Ángel Díaz-Ortiz、Sergio-A. Alonso de Diego
DOI:10.1039/c2gc35037h
日期:——
mediated by Grignard reagents (the Bodrouxreaction) is described. The procedure can be applied to a wide variety of primary and secondary amines and anilines, as well as to aromatic and aliphatic esters. The flow approach leads to improved yields and selectivities in the reaction, which has a sustainable purification procedure and a simple scale-up. This reaction represents an efficient and green alternative
The Selective<i>N</i>-Monoalkylation of Amides with Alkyl Halides in the Presence of Alumina and KOH
作者:Kazuaki Sukata
DOI:10.1246/bcsj.58.838
日期:1985.3
The effects of alumina impregnated with KOH (KOH/Al2O3) and a mixture of alumina and powdered KOH (KOH+Al2O3) have been examined using the alkylation of benzamide under various conditions. In each case, alkylation occurs exclusively in the pores of the alumina, the extent depending upon the alumina-pore size. For both yield and selectivity for N-monoalkylation, KOH+Al2O3 is superior to KOH/Al2O3. Dioxane is the best of the solvents employed. It is proposed that, in dioxane, an enolate-like species, (Remark: Graphics omitted.), exists as stable ion-pair aggregates, which are the true reactants in the pore. This method, using KOH/Al2O3 or KOH+Al2O3, has been applied to N-alkylation of the other amides, giving the N-monoalkylated products in substantial yields with extremely high selectivities. 2-Phenylacetamide is regioselectively N-monoalkylated in high yields. This regioselectivity is explained in terms of steric hindrance.
Niobium Pentachloride Promoted Conversion of Carboxylic Acids to Carboxamides: Synthesis of the 4-Aryl-1,2,3,4-tetrahydroisoquinoline Alkaloid Structures
作者:Claudio C. Lopes、Rosangela S. Lopes、Marcelo S. Nery、Renata P. Ribeiro
DOI:10.1055/s-2003-36823
日期:——
A practical method for the conversion of carboxylic acids to the corresponding carboxamides mediated by niobium pentachloride under mild conditions is described. The synthesis of the 4-aryl-1,2,3,4-tetrahydroisoquinoline alkaloid structures was accomplished via benzylic lithiation of N-methyl-3,4-dimethoxy-2-(4'-methoxybenzyl)benzamide.
C–N Coupling of Amides with Alcohols Catalyzed by N-Heterocyclic Carbene–Phosphine Iridium Complexes
作者:Sutthichat Kerdphon、Xu Quan、Vijay Singh Parihar、Pher G. Andersson
DOI:10.1021/acs.joc.5b01324
日期:2015.11.20
N-Heterocycliccarbene–phosphineiridiumcomplexes (NHC–Ir) were developed/found to be a highly reactive catalyst for N-monoalkylation of amides with alcohols via hydrogen transfer. The reaction produced the desired product in high isolated yields using a wide range of substrates with low catalyst loading and short reaction times.
Synthesis, X-Ray Crystallography, and Reactions of <i>N</i>-Acyl and <i>N</i>-Carbamoyl Succinimides
作者:Cassie A. Goodman、Joel B. Eagles、Leandre Rudahindwa、Christopher G. Hamaker、Shawn R. Hitchcock
DOI:10.1080/00397911.2012.690061
日期:2013.8.18
Abstract A collection of N-acyl and N-carbamoyl succinimides were prepared by acylation of succinimide with acyl chlorides or by ethylene dichloride (EDC) coupling of carboxylic acids. The x-ray crystal structures of N-benzoyl and N-p-nitrobenzoyl succinimides were determined. The N-acyl succinimides were effective in acylating primary amines, a secondary amine, and an aromatic amine. Supplemental