7515-80-2Relevant articles and documents
Bushweller et al.
, p. 3892,3893, 3899 (1974)
Dynamic Ureas with Fast and pH-Independent Hydrolytic Kinetics
Cai, Kaimin,Ying, Hanze,Cheng, Jianjun
supporting information, p. 7345 - 7348 (2018/06/11)
Low cost, high performance hydrolysable polymers are of great importance in biomedical applications and materials industries. While many applications require materials to have a degradation profile insensitive to external pH to achieve consistent release profiles under varying conditions, hydrolysable chemistry techniques developed so far have pH-dependent hydrolytic kinetics. This work reports the design and synthesis of a new type of hydrolysable polymer that has identical hydrolysis kinetics from pH 3 to 11. The unprecedented pH independent hydrolytic kinetics of the aryl ureas were shown to be related to the dynamic bond dissociation controlled hydrolysis mechanism; the resulting hindered poly(aryl urea) can be degraded with a hydrolysis half-life of 10 min in solution. More importantly, these fast degradable hindered aromatic polyureas can be easily prepared by addition polymerization from commercially available monomers and are resistant to hydrolysis in solid form for months under ambient storage conditions. The combined features of good stability in solid state and fast hydrolysis at various pH values is unprecedented in polyurea material, and will have implications for materials design and applications, such as sacrificial coatings and biomaterials.
A mild, copper-catalysed amide deprotection strategy: Use of tert-butyl as a protecting group
Evans, Vikki,Mahon, Mary F.,Webster, Ruth L.
supporting information, p. 7593 - 7597 (2014/12/10)
Mild methods for the deprotection of organic substrates are of fundamental importance in synthetic chemistry. A new room temperature method using a catalytic amount of Cu(OTf)2is reported. This allows use of the tert-butyl group as an amide protecting group. The methodology is also extended to Boc-deprotection.
