Palladium/Norbornene Chemistry in the Synthesis of Polycyclic Indolines with Simple Nitrogen Sources was written by Ghasemi, Mehran;Jafarpour, Farnaz;Habibi, Azizollah. And the article was included in Synthesis in 2020.Application In Synthesis of 1,3-Dicyclohexylurea This article mentions the following:
An efficient procedure has been developed to synthesize indoline derivatives, e.g., I, through a palladium-catalyzed Heck reaction/C-H activation/dual amination cascade in one pot. This constitutes the first intermol. catalytic approach to directly access N-alkylindolines with a broad substrate scope in the absence of any ligands. This method highlights the use of readily available amines and ureas as the required nitrogen sources in building up the indoline core. In the experiment, the researchers used many compounds, for example, 1,3-Dicyclohexylurea (cas: 2387-23-7Application In Synthesis of 1,3-Dicyclohexylurea).
1,3-Dicyclohexylurea (cas: 2387-23-7) belongs to amides. Because of the greater electronegativity of oxygen, the carbonyl (C=O) is a stronger dipole than the N–C dipole. The presence of a C=O dipole and, to a lesser extent a N–C dipole, allows amides to act as H-bond acceptors. Amides can be recrystallised from large quantities of water, ethanol, ethanol/ether, aqueous ethanol, chloroform/toluene, chloroform or acetic acid. The likely impurities are the parent acids or the alkyl esters from which they have been made. The former can be removed by thorough washing with aqueous ammonia followed by recrystallisation, whereas elimination of the latter is by trituration or recrystallisation from an organic solvent.Application In Synthesis of 1,3-Dicyclohexylurea
Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics