5669-09-0Relevant articles and documents
Cationic polymerization of isobutyl vinyl ether coinitiated with heteropolyacid or its salts in aqueous medium
Huang, Qiang,Wu, Yixian,Dan, Jie
, p. 546 - 556 (2013)
The suspension cationic polymerization of isobutyl vinyl ether (IBVE) in aqueous medium could be achieved by using H3PW12O 40, AlPW12O40, FePW12O40, K3PW12O40, or Na3PW 12O40 as efficient water-tolerant coinitiators in the presence of HCl. The addition reaction of IBVE with H2O occurred to form IBVE-H2O adduct and then subsequent decomposition immediately took place or turned to acetaldehyde diisobutyl acetal (A) in the presence of AlPW12O40, and (A) decomposed rapidly to form 2-isobutanol (B) and acetaldehyde (C). Cationic polymerization of IBVE in aqueous medium was promoted greatly with increasing HCl concentration and proceeded extremely rapidly to get high polymer yield even at low concentration of AlPW 12O40 of 0.3 mM. A sufficient amount of HCl was needed to decrease the hydrolysis of initiator IBVE-HCl and to accelerate the polymerization in aqueous medium simultaneously. The yield and molecular weight of poly(IBVE) increased with increasing concentrations of HCl and AlPW 12O40 or with decreasing temperature. The isotactic-rich poly(IBVE)s with m diad of around 60%, having Mn of 1200-4500 g mol-1 and monomodal molecular weight distribution could be obtained via cationic polymerization of IBVE in aqueous medium. This is the first example of cationic polymerization of IBVE in aqueous medium coinitiated by heteropolyacid and its salts.
2-(2,4,5-TRIMETHYLCYCLOHEX-2-EN-1-YL)ACETALDEHYDE AND DERIVATIVES AND THEIR USE AS AROMA CHEMICALS
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Page/Page column 74; 77-78, (2021/01/29)
The present invention relates to 2-(2,4,5-trimethylcyclohex-2-en-1-yl)acetaldehyde and derivatives thereof, to a process for preparing said compounds, to the use of 2-(2,4,5- trimethylcyclohex-2-en-1-yl)acetaldehyde or a specific derivative thereof or of mixtures of said compounds or of a stereoisomer thereof or of a mixture of two or more stereoisomers thereof as aroma chemicals; to the use of 2-(2,4,5-trimethylcyclohex-2- en-1-yl)acetaldehyde or a specific derivative thereof for modifying the scent character of a fragranced composition; to compositions containing 2-(2,4,5-trimethylcyclohex-2- en-1-yl)acetaldehyde or a specific derivative thereof or a mixture of said compounds or a stereoisomer thereof or a mixture of two or more stereoisomers thereof; and to a method of preparing a fragranced composition or for modifying the scent character of a fragranced composition, comprising incorporating 2-(2,4,5-trimethylcyclohex-2-en-1-yl)- acetaldehyde or a specific derivative thereof or a mixture of said compounds or a stereoisomer thereof or a mixture of two or more stereoisomers thereof into said composition.
A HIGHLY DIASTEREOSELECTIVE SYNTHESIS OF DL-OLEANDROSE
Berti, G.,Catelani, G.,Colonna, F.,Monti, L.
, p. 3067 - 3072 (2007/10/02)
Racemic oleandrose (2,6-dideoxy-3-O-methyl-arabino-hexose) has been obtained starting from the Diels-Alder adduct between 4-methoxy-3-buten-2-one and isobutyl vinyl ether, which was converted into a mixture of the isobutyl β- and α-oleandrosides through hydroboration-oxidation.The latter reaction is highly diastereoselective since attack by borane takes place exclusively anti to the OMe group; none of the diastereoisomeric cymarosides are formed.The only side-products are small amounts of the isobutyl β- and α-amicetosides formed by a demethoxylation occuring during the hydroboration step.
