85600-10-8Relevant articles and documents
Hindered urea bond: A bilaterally responsive chemistry to hydrogen peroxide
Ying, Hanze,Yang, Yingfeng,Cai, Kaimin,Cheng, Jianjun
supporting information, p. 728 - 731 (2019/01/24)
As a type of safe, clean, and bio-relevant oxidant, hydrogen peroxide has been widely used as a trigger in the design of stimuli-responsive materials. Hindered urea bond (HUB) is a type of dynamic covalent bond which can reversibly dissociate into isocyanate and amine. Quenching of isocyanate or amine will shift the equilibrium and facilitate the degradation of HUB bond. Herein, we report that one of the HUB moiety – 1,1-tert-butylethylurea (TBEU) can react with hydrogen peroxide (H2O2) resulting in two opposing outcomes. Perhydrolysis of isocyanate and oxidation of amine lead to the bond fracture, while formation of urethane product with an oxygen inserted into the original TBEU structure was also observed giving a stabilized form of linkage. More precise kinetic control of the two distinct pathways are expected to make hydrogen peroxide a trigger to either degrade or fix the HUB based polymeric materials.
First catalyst-free CO2 trapping of: N -acyliminium ions under ambient conditions: Sustainable multicomponent synthesis of thia- and oxazolidinyl carbamates
Franz, Max,Martens, Jürgen,Stalling, Timo,Steinert, Henning
, p. 6914 - 6926 (2018/10/02)
The first trapping of N-acyliminium ions by in situ generated carbaminic acid (product of carbon dioxide (CO2) and amine) is reported. This catalyst-free reaction provides a convenient and feasible approach to prepare N-acyl thia- and oxazolidi
Parallel synthesis of ureas and carbamates from amines and CO2 under mild conditions
Peterson, Scott L.,Stucka, Sabrina M.,Dinsmore, Christopher J.
supporting information; experimental part, p. 1340 - 1343 (2010/06/15)
"Chemical Equation Presented" A mild and efficient library synthesis technique has been developed for the synthesis of ureas and carbamates from carbamic acids derived from the DBU-catalyzed reaction of amines and gaseous carbon dioxide. Carbamic acids derived from primary amines reacted with Mitsunobu reagents to generate isocyanates in situ which were condensed with primary and secondary amines to afford the desired ureas. Similarly, carbamic acids from secondary amines reacted with alcohols activated with Mitsunobu reagents to form carbamates.