3396-11-0Relevant articles and documents
Carbon dioxide utilization via carbonate-promoted C-H carboxylation
Banerjee, Aanindeeta,Dick, Graham R.,Yoshino, Tatsuhiko,Kanan, Matthew W.
, p. 215 - 219 (2016/03/22)
Using carbon dioxide (CO2) as a feedstock for commodity synthesis is an attractive means of reducing greenhouse gas emissions and a possible stepping-stone towards renewable synthetic fuels. A major impediment to synthesizing compounds from CO2 is the difficulty of forming carbon-carbon (C-C) bonds efficiently: although CO2 reacts readily with carbon-centred nucleophiles, generating these intermediates requires high-energy reagents (such as highly reducing metals or strong organic bases), carbon-heteroatom bonds or relatively acidic carbon-hydrogen (C-H) bonds. These requirements negate the environmental benefit of using CO2 as a substrate and limit the chemistry to low-volume targets. Here we show that intermediate-temperature (200 to 350 degrees Celsius) molten salts containing caesium or potassium cations enable carbonate ions (CO32-) to deprotonate very weakly acidic C-H bonds (pKa > 40), generating carbon-centred nucleophiles that react with CO2 to form carboxylates. To illustrate a potential application, we use C-H carboxylation followed by protonation to convert 2-furoic acid into furan-2,5-dicarboxylic acid (FDCA) - a highly desirable bio-based feedstock with numerous applications, including the synthesis of polyethylene furandicarboxylate (PEF), which is a potential large-scale substitute for petroleum-derived polyethylene terephthalate (PET). Since 2-furoic acid can readily be made from lignocellulose, CO32--promoted C-H carboxylation thus reveals a way to transform inedible biomass and CO2 into a valuable feedstock chemical. Our results provide a new strategy for using CO2 in the synthesis of multi-carbon compounds.
Azetidines
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Page/Page column 33, (2008/12/08)
The invention relates to EP2 antagonist azetidines of formula (I) wherein Ar, R1, X, and Z are as defined herein, to their use in medicine, particularly in the treatment of endometriosis and/or uterine fibroids, to intermediates useful in their synthesis, and to compositions containing them.
Nucleophilic addition to acetylenes in superbasic catalytic systems: XI. Transformations of alkali metal hydroxides during vinylation of 1-heptanol with acetylene under elevated pressure
Oparina,Parshina,Khil'ko,Gorelova,Preiss,Henkelmann,Trofimov
, p. 1553 - 1558 (2007/10/03)
Base-catalyzed addition of 1-heptanol to acetylene under elevated pressure of the latter is accompanied by side processes including formation of carboxylic acid salts (alkali metal heptanoates and acetates) with liberation of hydrogen and acetylene polyme
