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    Abstract Nitro groups on thiophene ring systems are transformed directly into acetylamino functions in yields of 61–82% by means of a mixture of iron, acetic acid, and acetic anhydride at 50–105°. When a bromo suhstituent is also present on the ring partial hydrodebromination occurs during the reaction.
    Citations (22)
    The highly practical acetylation of free nucleosides is achieved using acetic anhydride/acetic acid as a reusable solvent and acetylating regent. A series of nucleosides, including ribosyl, deoxyribosyl, arabinosyl, acyclic and pyranosyl, and many clinical drugs were acetylated efficiently, even on large scale (200 g).
    Citations (1)
    A variety of alcohols are acetylated and formylated efficiently with acetic acid and ethyl formate in the presence of catalytic amounts of Bi(III) salts such as BiCl 3 , Bi(TFA) 3 and Bi(OTf) 3 . BiCl 3 and Bi(OTf) 3 are also effective catalysts for acetylation of phenols. All of these catalysts are ineffective in formylation of phenols. Selective acetylation and formylation of alcohols in the presence of phenols is an additional advantage of this procedure.
    Formylation
    Ethyl formate
    Methyl formate
    Citations (21)
    Abstract Nowadays Celluloseacetate is mainly produced with the acetic acid process. After an activation with acetic acid and sulfuric acid the acetylation of the cellulose starts by adding acetic anhydride. The temperature and the catalyst concentration play an important role for the reaction. Beneath acetylation also degradation of the cellulose chains occurs. In the first step of the process cellulosetriacetate is formed. In a second step, the hydrolysis, several acetyl groups are removed to achieve an average degree of substitution of 2,5. The water content in this step influences the acetyl distribution.
    Hydroxyl value
    Cellulose acetate
    Degradation
    Citations (71)