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Sauron
International Hazard
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The site shows in US$ for me, go figure. 50 g $141 and change, but, that ought to be about 75 Euros. Anyway too damned much, for something you can
make easily from the nitroaniline for 1/20 the cost.
Sic gorgeamus a los subjectatus nunc.
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garage chemist
chemical wizard
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Even the whole process starting from benzene would be feasible.
Detailed procedures are readily available for each single step.
1,3-dinitrobenzene from nitrobenzene uses fuming HNO3/H2SO4 at around 100°C and requires proper purification to remove the byproduct
1,2-dinitrobenzene which is formed to the extent of about 10%.
Selective reduction to m-nitroaniline can be done with sulfide, that's the most reliable method since it is well documented.
Diazotation and heating to form m-nitrophenol gives exceptionally good yields for such a reaction.
The crucial information that we need is: Which isomer from the formylation is extracted by NaHSO3? Is it the wanted 6-nitrosalicylaldehyde, or the
useless other isomer?
One could theoretically try it out oneself, it's just a yes-no question to be answered. But proper identification of the obtained compounds would be
the main concern.
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Sauron
International Hazard
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Aren't the different isomeric nitrosalicaldehydes characterized in the lit.?
Crystallize till pure by tlc than take a mp. Or that of a known derivative. Like the 2,4-dinitrophenylhydrazone.
Sic gorgeamus a los subjectatus nunc.
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Nicodem
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I think the major product is the desired 6-hydroxy-2-nitrobenzaldehyde since in one of the abstracts they isolate it by a single recrystallization
which is hardly possible if you would have a mixture of regioisomers of a ratio less than about 2 : 1 for example. Quite probably they don't do any
real "extraction" with bisulfite. More likely they just used the bisulfite method to purify the aldehyde and recovered just one product (due to the
other being present only in small amounts and being washed off at the bisulfite adduct isolation stage).
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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