Sun, Dalei et al. published their research in Catalysts in 2018 | CAS: 2387-23-7

1,3-Dicyclohexylurea (cas: 2387-23-7) belongs to amides. Amides are pervasive in nature and technology. Proteins and important plastics like Nylons, Aramid, Twaron, and Kevlar are polymers whose units are connected by amide groups (polyamides); these linkages are easily formed, confer structural rigidity, and resist hydrolysis. Amides are not in general accessible by the direct condensation of amines with carboxylic acids for two reasons: first, both components are readily deactivated by a transfer of a proton from the acid to the amine and second, the hydroxy unit on the carbonyl of the acid is a relatively poor leaving group. Nevertheless, the formation of five- and six-membered rings is often surprisingly simple provided that other factors can be brought into play to assist in the condensation.Quality Control of 1,3-Dicyclohexylurea

One-pot synthesis of N,N’-dialkylureas via carbonylation of amines with CO2 applying Y0.08Zr0.92O1.96 mixed oxide (YSZ-8) as a heterogeneous catalyst was written by Sun, Dalei;Xie, Kaihong;Fang, Yanxiong;Yang, Xianghua. And the article was included in Catalysts in 2018.Quality Control of 1,3-Dicyclohexylurea This article mentions the following:

One-pot synthesis of N,N’-dialkylureas were successfully achieved from catalytic carbonylation of aliphatic primary amines with CO2 as the carbon source and Y0.08Zr0.92O1.96 mixed oxide (Yttria-stabilized zirconia, YSZ-8) as the heterogeneous catalyst. The yield of the target product was obtained up to 80.60% from a 48 h reaction with an aliphatic primary amine and 3.0 MPa CO2 in N-methyl-2-pirrolidinone at 160 °C. A multi-pronged mechanistic study was carried out where factors that might influence the reaction efficiency were studied, including catalyst structure, substrates basicity, CO2 pressure, solvent polarity and reaction time. The presence of oxygen vacancies in YSZ-8 was found to be essential for the carbonylation process by creating addnl. reduction potential for the activation of CO2 which would lead to the key intermediate species. In the experiment, the researchers used many compounds, for example, 1,3-Dicyclohexylurea (cas: 2387-23-7Quality Control of 1,3-Dicyclohexylurea).

1,3-Dicyclohexylurea (cas: 2387-23-7) belongs to amides. Amides are pervasive in nature and technology. Proteins and important plastics like Nylons, Aramid, Twaron, and Kevlar are polymers whose units are connected by amide groups (polyamides); these linkages are easily formed, confer structural rigidity, and resist hydrolysis. Amides are not in general accessible by the direct condensation of amines with carboxylic acids for two reasons: first, both components are readily deactivated by a transfer of a proton from the acid to the amine and second, the hydroxy unit on the carbonyl of the acid is a relatively poor leaving group. Nevertheless, the formation of five- and six-membered rings is often surprisingly simple provided that other factors can be brought into play to assist in the condensation.Quality Control of 1,3-Dicyclohexylurea

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics