- Puzzling formation of bisimidazole derivatives from hexachloroacetone and diamines
-
The reaction of hexachloroacetone with different diamines leads to formation of the bisimidazole derivatives 2, 3, anf 4, a process which is facilitated by sonication of the reaction mixtures.
- Rezende, Marcos Caroli,Dall'Oglio, Evandro Luiz,Zucco, Cesar
-
-
Read Online
- Efficient Non-Catalytic Carboxylation of Diamines to Cyclic Ureas Using 2-Pyrrolidone as a Solvent and a Promoter
-
Carboxylation reactions of diamines were found to proceed rapidly and non-catalytically, producing corresponding cyclic ureas in excellent yields and selectivities when 2-pyrrolidone (2-PY) was used as a solvent. A similar promoting effect with 2-PY was also observed for the carboxylation of monoamines by carbon dioxide (CO2). Most notably, the carboxylation reactions of mono- and diamines conducted in 2-PY afforded 2–4 times higher yields of corresponding dialkyl ureas and cyclic ureas compared with those in N-methyl-2-pyrrolidone (NMP). Such a dramatic promoting effect using 2-PY is believed to be associated with the multiple hydrogen bonding interactions between 2-PY and the CO2-containing species of amines. Due to such favorable interactions, carboxylation reactions seem to be more facilitated in 2-PY than in NMP. (Figure presented.).
- Hwang, Junhyeok,Han, Donggu,Oh, Jin Joo,Cheong, Minserk,Koo, Hyun-Joo,Lee, Je Seung,Kim, Hoon Sik
-
-
Read Online
- CARBON DIOXIDE-REVERSIBLY-PROTECTED CHAIN EXTENSION-CROSSLINKING AGENT AND PREPARATION METHOD AND USE THEREOF
-
Carbon dioxide-reversibly-protected chain extension-crosslinking agents and a preparation method and use thereof are disclosed, The carbon dioxide-reversibly-protected chain extension-crosslinking agents have chemical structures represented by Formula I, Formula II, Formula III or Formula IV, wherein, n, m and p are integers, R is either OCH2CH(CH3) or OCH2CH2, 1≤n≤20, 1≤m≤10, and 1≤p≤10.
- -
-
Paragraph 0093; 0094
(2021/10/30)
-
- PREPARING METHOD OF SOLID CARBAMIC ACID DERIVATIVES
-
The present disclosure relates to a preparation method for powder of a carbamic acid derivative, which includes reacting a liquid amine derivative with carbon dioxide at a temperature in a range of from about ?30° C. to about 500° C. at a pressure in a range of from about 0.3 MPa to about 100 MPa. In addition, the present disclosure relates to a reduction method for powder of a carbamic acid derivative to a liquid amine derivative and carbon dioxide, which includes dissolving powder of the carbamic acid derivative prepared in a solvent; refluxing the carbamic acid derivative at a temperature in a range of from about 30° C. to about 100° C.; and evaporating the solvent. The preparation method for a carbamic acid derivative powder according to the present disclosure enables easy conversion into pure powder of solid carbamic acid derivative without by-products and can remarkably reduce time and energy required for solidification by reacting carbon dioxides and amines with carbon dioxides in high pressure conditions without the use of a solvent. In addition, the prepared solid compounds can be used as a liquid amine substitute or used in a carbamic acid derivative form as necessary.
- -
-
Paragraph 0042-0046
(2014/03/24)
-
- Direct synthesis of imines via solid state reactions of carbamates with aldehydes
-
Various solid carbamates were prepared from the reactions of liquid amines with carbon dioxide in an autoclave and these carbamates were used as stable, efficient alternatives for toxic liquid amines. Solid-state grinding of carbamates and aldehydes, using a mortar and pestle, produced imines as the sole products in greater than 97% yields. Complete conversions were generally accomplished within a day at 25 °C without using solvents or additives. Reaction rates were drastically enhanced upon increasing the reaction temperature. In contrast, reactions of aldehydes with liquid amines in the presence of solvent or in neat conditions afforded imines in moderate yields along with by-products.
- Lee, Byeongno,Lee, Kyu Hyung,Lim, Byung Wook,Cho, Jaeheung,Nam, Wonwoo,Hur, Nam Hwi
-
supporting information
p. 389 - 394
(2013/05/08)
-
- Orthoamides and iminium salts, LXX [1]. Capturing of carbon dioxide with organic bases (Part 1) - Reactions of diamines with carbon dioxide
-
The alkylammonium alkylcarbamates 2, 4a,b, 14 were prepared from the amines 1, 3a,b, 13 and CO2. The crystal structures of 2 and 4b show carbamate anions, which are connected by N-H?O hydrogen bonds to form centrosymmetric dimers. The zwitterionic carbamates 7a,b, 8a,b and 11 are formed in the reactions of the diamines 6a,b and 10 with CO2. The crystal structures of 7a and 8b show strong intermolecular hydrogen bonds involving water molecules, the ammonium and the carbamate groups. In these compounds the molecules are interconnected in an extended two- or three-dimensional network. Due to the absence of crystal water molecules, the structure of 11 contains intermolecular hydrogen bonds involving the ammonium and the carbamate group in double-stranded chains. The diamines 17a,b react with CO2 to give the zwitterionic carbamates 18a,b.
- Tiritiris, Ioannis,Kantlehner, Willi
-
experimental part
p. 164 - 176
(2011/05/07)
-
- CARBONYLATION OF AMINES AND DIAMINES CATALYZED BY NICKEL CARBONYL
-
The carbonylation of amines and diamines was carried out using nickel carbonyl as the catalyst. reaction of butylamine, diethylamine, and diphenylamine with carbon monoxide all lead exclusively to the corresponding formamide derivative.Benzylamine reacts with carbon monoxide to yield urea and 1,2-diphenylethane.Diamines such as ethylenediamine, 1,2-diaminopropane, and 1,3-propylenediamine react to yield a cyclic condensation product, a cyclic uren, and a carbamic acid.
- Martin, Wilbur E.,Farona, Michael F.
-
p. 393 - 397
(2007/10/02)
-
