Presence Of Ethoxide Research Articles

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OPINION Reactions ShareShare onFacebookTwitterWechatLinked InRedditEmail C&EN, 2020, 98 (10), p 3March 16, 2020Cite this:C&EN 98, 10, 3Letters to the editor Lab allergies While working as a postdoctoral fellow at the Ohio State University in Columbus, 1974–76, in the laboratory of Garfield P. Royer, we routinely used the water soluble carbodiimide 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride for enzyme immobilizations. It was a typical academic lab of the time and somewhat grubby. One day I decided to wipe down a hood and used a sponge and water. I did not wear gloves. Big mistake! My hands and palms turned a purple red as if they had been burned. A couple of hours later I developed hives over much of my body, which itched a lot. I went to the emergency room and was treated for an allergic reaction. Fortunately, my lungs were not involved. Thereafter, I was extremely cautious with the carbodiimide and had no further problems. It never occurred to me to say much about it at the time. Thank you for publishing this warning on allergic reactions from working with coupling agents (C&EN, Jan. 13, 2020, page 4).Frederick A. Liberatore Leicester, MassachusettsI consider Carolyn Bertozzi to be the finest carbohydrate chemist of my lifetime. Now a retired (50-year American Chemical Society member) sugar/polysaccharide chemist, I recognize the range and significance of her accomplishments. That said, I believe that the phrase under the title of her profile in the Feb. 3 issue (“As she turns from building biological tools to building biotech companies”) understates her current status and impact. While building companies, she and her team also not only continue to develop tools but also advance knowledge in this extremely complex area of glycoscience. It is a pleasure to follow and learn from her research. Dr. Bertozzi was brave to enter this area “on the ground floor.”Landis W. Doner Wyndmoor, Pennsylvania Corrections Feb. 17, 2020, page 7: The news story about unexpected haze chemistry in China described the chemistry involving nitrous acid (HONO) and sulfur dioxide incorrectly. HONO doesn’t reduce SO2 to sulfates; it oxidizes SO2.Feb. 17, 2020, page 9: In the Sketch Chemistry cartoon, the depicted mechanism probably favors elimination of HBr in the presence of ethoxide instead of the substitution shown. Ethanol would be a more appropriate reactant for that substitution.Feb. 24, 2020, page 18: In the feature story about biobased aromatics, Arend Jan Zeeuw’s family name is Zeeuw, not Jan Zeeuw. Zeeuw’s company, Huntsman, is working with multiple partners, not one, to use black liquor from the paper industry to make aromatic compounds. The figure for global black liquor production should be more than 140 million metric tons, not just 140 million, and Huntsman does not have a specific target amount of biobased benzene it wants to use to make isocyanates. Bloom Biorenewables has raised more than $1.7 million from investors, not $66,000.

ChemInform Abstract: Ipso‐Substitution by Alkoxide Ions in Photolysis of Triarylvinyl Halides. Firm Evidence for Intervention of Vinyl Cations.

AbstractThe triarylvinyl bromides (I) rearrange upon photolysis in the presence of ethoxide and ethanol (II) to give the allene derivatives (III) representing the ipso adducts, together with the triarylvinyl ethyl ethers (IV).

ChemInform Abstract: METHYLATION OF PYRIMIDINE DERIVATIVES

AbstractDas Pyrimidindion (I) reagiert mit l Mol Methyliodid zur Verbindung (II), mit 2 Mol dagegen zu einem Gemisch der Isomeren (III) und (IV).

Methylation of pyrimidine derivatives

A mixture of isomers that differ with respect to the position of the methyl group is formed in the methylation of 5,5-diethyl-6-imino-5,6-dihydro[1H, 3H]pyrimidine-2,4-dione with excess methyl iodide in the presence of ethoxide. Isomerization of the Dimroth-rearrangement type was observed. The mass spectra of the isomers are examined, and the IR spectra of the tautomeric forms are discussed.

Heterocyclic imines and amines. Part XV. Reactions of hydrazines with 1,3-di-iminoisoindoline and related compounds

The ring-expansion reactions of 1,3-di-iminoisoindoline with hydrazine are detailed. In the cold, 1,4-diamino-phthalazine is given; in boiling butanol, 1,4-dihydrazinophthalazine; and under reflux, bis-(4-aminophthalazin-1-yl) together with phthalazin-1 (2H)-one, which is the major product at higher temperature. Methylhydrazine likewise effects ring expansion to give 4-amino-1,2-dihydro-1-imino-2-methylphthalazine, which is hydrolysed to 4-amino-2-methylphthalazin-1 (2H)-one, also obtained from 3-iminoisoindolinone and methylhydrazine and by methylation of 4-aminophthalazin-1 (2H)-one. Phenylhydrazine merely displaces an exocyclic imino-group of di-iminoisoindoline and of 3-iminoisoindolinone to yield phenylhydrazonoisoindolines or tautomers. Hydrazine adds to phthalonitrile in the presence of ethoxide, and reacts with monothiophthalimide, to give hydra-zonoisoindolines which readily isomerise to aminophthalazines. The structures of the benzoyl derivatives of 4-aminophthalazinone have been established.