60314-07-0Relevant academic research and scientific papers
Process for producing rhein and diacerhein
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, (2008/06/13)
The following description sets forth a process for producing rhein, diacerhein and other diacyl derivatives thereof, which comprises the following steps: treatment of a diphenylketone STR1 in which R1 is --OR', --NR'R", --SR', where R' and R" are H, an alkyl or aromatic group; R2 is H or a protective group, R3 is --OH or C1 -C4 alkyl, with an acid or superacid to give a 1-aminoanthraquinone derivative, diazotisation, replacement of the --NH2 group by --OH, optional removal of the protective group, and acylation.
Process for producing rhein and diacerhein
-
, (2008/06/13)
The following description sets forth a process for producing rhein, diacerhein and other diacyl derivatives thereof, which comprises the following steps: treatment of a diphenylketone in which R1is -OR', -NR'R'', -SR', where R' and R'' are H, an alkyl or aromatic group; R2is H or a protective group. R3is -OH or C1-C4alkyl, with an acid or superacid to give a 1-aminoanthraquinone derivative, diazotisation, replacement of the -NH2group by -OH, optional removal of the protective group, and acylation.
Facile Interconversion of the Isomeric Acid Chlorides Derived from Half Methyl Esters of 3-Methoxyphthalic Acid
Gupta, Dahmendra N.,Hodge, Philip,Hurley, Peter N.
, p. 391 - 394 (2007/10/02)
The isomeric acid chlorides obtained by treating the half methyl esters of 3-methoxyphthalic acid with thionyl chloride interconvert so readily that it is not practical to isolate one acid chloride free of the other.At equilibrium the main isomer is the a
