96820-10-9Relevant academic research and scientific papers
O-acetylation: Synthesis of acetylated phenols from aryl-methyl ethers over boron alkoxides
Balaydin, Halis T.
scheme or table, p. 238 - 240 (2012/09/08)
A new acetylation procedure has been applied to 13 aryl-methyl ethers using boron chemistry. In this procedure, demethylation of aryl-methyl ethers and acetylation of the resulting phenols were combined into one procedure in order to shorten the number of stages and to achieve easy purification. Eleven known with/without bromine and two new [bis(3,4-diacetoxyphenyl)methanone and 5,5'-methylenebis(1,2-diacetoxy-3,4-dibromobenzene) (a natural bromophenol's acetylated derivative)] acetylated arene compounds were synthesised from their methoxy derivatives by this method. The effectiveness of the method was illustrated by producing an acetylated natural bromophenol from its methyl ether. The phenol form was obtained by hydrolysing the acetylated natural bromophenol. Thus, the advantage of this method in the natural product chemistry of phenolic compounds was confirmed.
Bromophloroglucinols and their methyl ethers
Kiehlmann, E.,Lauener, R. W.
, p. 335 - 344 (2007/10/02)
All 16 bromination products of phloroglucinol and its methyl ethers, as well as five bromoresorcinols and three of their dimethyl ethers, were synthesized and analyzed by nuclear magnetic resonance spectroscopy.Two or three equivalents of bromine convert phloroglucinol to di- and tribromophloroglucinol, 5-methoxyresorcinol to the tri- and 2,4-dibromo, 3,5-dimethoxyphenol to the tri- and 2,6-dibromo, and 1,3,5-trimethoxybenzene to the dibromo compound.With one equivalent of bromine, 3,5-dimethoxyphenol reacts preferentially at C-2 while 5-methoxyresorcinol gives both monobromo isomers.Partial debromination with sodium sulfite yields successively 2,4-dibromo- and 2-bromo-5-methoxyresorcinol from the tribromo compound but fails with brominated 3,5-dimethoxyphenol.In the resorcinol series, C-2 is invariably the least reactive position. 4,6-Dibromo-5-methoxyresorcinol and 2,4-dibromo-3,5-dimethoxyphenol are accessible by methylation of dibromophloroglucinol, obtained from 3,5-dibromo-2,4,6-trihydroxybenzoic acid by decarboxylation.In contrast to resorcinol and tribromoresorcinol, the partial bromination of pholoroglucinol and debromination of tribromopholoroglucinol are not selective.The 13Cnmr spectra of bromophloroglucinol methyl ethers show characteristic downfield shifts for methoxy groups orthogonal to the aromatic ring plane.
