Overcoming Barriers in Polycarbonate Synthesis: A Streamlined Approach for the Synthesis of Cyclic Carbonate Monomers
作者:Eddy W. P. Tan、James L. Hedrick、Pedro L. Arrechea、Tim Erdmann、Vivien Kiyek、Simon Lottier、Yi Yan Yang、Nathaniel H. Park
DOI:10.1021/acs.macromol.0c02880
日期:2021.2.23
Accessing cyclic carbonate monomers on a large scale is critical for the development of any new carbonate-based materials platform. The synthesis of carbonate monomers can be a challenging and tedious endeavor requiring multiple synthetic steps and purifications. To address this, we report a drastically improved process for the synthesis of carbonate monomers via a two-step route that avoids the use
BIODEGRADABLE BLOCK POLYMERS FOR DRUG DELIVERY, AND METHODS RELATED THERETO
申请人:Hedrick James
公开号:US20110152167A1
公开(公告)日:2011-06-23
A biodegradable block copolymer is disclosed, comprising a hydrophilic block derived from a polyether alcohol; and a hydrophobic block comprising a first repeat unit derived by ring opening polymerization of a first cyclic carbonyl monomer initiated by the polyether alcohol, the first repeat unit comprising a side chain moiety comprising a functional group selected from the group consisting of urea groups, a carboxylic acid groups, and mixtures thereof. No side chain of the hydrophobic block comprises a covalently bound biologically active material. The block copolymer self-assembles in water forming micelles suitable for sequestering a biologically active material by a non-covalent interaction, and the block copolymer is 60% biodegraded within 180 days in accordance with ASTM D6400.
Selective pyrolysis of bifunctional compounds: gas-phase elimination of carbonate–ester functionalities
作者:Talal F. Al-Azemi、Hicham H. Dib、Nouria A. Al-Awadi、Osman M.E. El-Dusouqui
DOI:10.1016/j.tet.2008.01.002
日期:2008.4
Compounds containing both carbonate and ester functionalities were synthesized and then subjected to online-GC gas-phasepyrolysis. The carbonate groups were cleaved selectively in all elimination reactions. The end products of the reaction were found to be affected by the nature of the substrate. The presence of hydrogen and carbonyl substituents on the carbon β to the carbonate group resulted in
Selective monobenzylation of 2,2-bis(hydroxymethyl)propionic acid (bis-MPA) to yield an AB linear monomer and analogous linear oligomers
作者:Joseph A. Giesen、Scott M. Grayson
DOI:10.1016/j.tetlet.2020.152016
日期:2020.6
synthesis utilizes a generic acid-catalyzed esterification of bis-MPA to the ethylester. Subsequently, a selective mono-benzylation mediated by silver(I) oxide affords the monobenzyl ether of the ethylester. Finally, a simple base hydrolysis of monobenzyl ether ethylester yields 3-(benzyloxy)-2-(hydroxymethyl)-2-methylpropanoic acid, the AB monomer. This synthesis was utilized to generate gram quantities
ANTIMICROBIAL HYDROGELS, METHODS OF PREPARATION THEREOF, AND ARTICLES THEREFROM
申请人:Coady Daniel Joseph
公开号:US20120231060A1
公开(公告)日:2012-09-13
A covalently crosslinked hydrogel comprises a) three or more divalent poly(alkylene oxide) chains P′ covalently linked at respective first end units to a branched first core group C′, b) three or more divalent poly(alkylene oxide) chains P″ covalently linked at respective first end units to a branched second core group C″, the chains P″ comprising respective second end units which are covalently linked to between 0% and 100% of respective second end units of chains P′ by divalent linking groups L″, and c) at least one pendant cationic block copolymer chain A′-B′. A′-B′ comprises i) a divalent block A′ comprising a poly(alkylene oxide) backbone chain having an end unit covalently linked to a second end unit of one of the chains P′ by a divalent linking group L′, and ii) a monovalent block B′ comprising a first repeat unit, the first repeat unit comprising a backbone carbonate group and a cationic side chain group.