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Are there any sources for tabulated Rf-values, especially 1-phenylazo-2-naphthol?
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+ Biochemistry
+ Chromatography
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Michael Ward
Are there any sources for tabulated Rf-values, especially 1-phenylazo-2-naphthol?
Did you react aniline (or its hydrochloride) with sodium nitrite in the presence of 2-naphthol?
I'm afraid there will not be any table with $R_\mathrm{f}$ values.
These values are not only dependent on the compounds and the mobile phases, but also on the stationary phase: e.g. silica, aluminium oxide, etc.
Your best option is to use reference samples and measure the $R_\mathrm{f}$ value yourself for the conditions you want to apply or transfer from TLC to column chromatography.
My suggestion is to collect the crude reaction product (Büchner funnel, etc.) dry it, note the yield and measure the melting point.
For purification, recrystallize from ethanol. You should receive red needles with a melting point of $\pu{134 ^\circ C}$.
NOTE: Wear proper protection when handling the azo dye, which is a cancer suspect.
Did you react aniline (or its hydrochloride) with sodium nitrite in the presence of 2-naphthol?
I'm afraid there will not be any table with $R_\mathrm{f}$ values.These values are not only dependent on the compounds and the mobile phases, but also on the stationary phase: e.g. silica, aluminium oxide, etc.Your best option is to use reference samples and measure the $R_\mathrm{f}$ value yourself for the conditions you want to apply or transfer from TLC to column chromatography.
My suggestion is to collect the crude reaction product (Büchner funnel, etc.) dry it, note the yield and measure the melting point.
For purification, recrystallize from ethanol. You should receive red needles with a melting point of $\pu{134 ^\circ C}$.
NOTE: Wear proper protection when handling the azo dye, which is a cancer suspect.
I agree 100%. Even if such tables existed, depending on how accurately you measure the solvents ratio, the $R_\mathrm{f}$ will change slightly. So the best bet is to leave a little room on the TLC plate and spot reference samples for comparison.More
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$R_\mathrm{f}$ is sensitive to particular stationary phase, up to having different $R_\mathrm{f}$ on different plates. Traditionally, it is done comparing $R_\mathrm{f}$ of freshly acquired sample and obtained previously in a different manner reference.
However, I agree with Klaus, use melting point of characterisation if possible.
$R_\mathrm{f}$ is sensitive to particular stationary phase, up to having different $R_\mathrm{f}$ on different plates. Traditionally, it is done comparing $R_\mathrm{f}$ of freshly acquired sample and obtained previously in a different manner reference.
However, I agree with Klaus, use melting point of characterisation if possible.
Did you react aniline (or its hydrochloride) with sodium nitrite in the presence of 2-naphthol?
I'm afraid there will not be any table with $R_\mathrm{f}$ values. These values are not only dependent on the compounds and the mobile phases, but also on the stationary phase: e.g. silica, aluminium oxide, etc. Your best option is to use reference samples and measure the $R_\mathrm{f}$ value yourself for the conditions you want to apply or transfer from TLC to column chromatography.
My suggestion is to collect the crude reaction product (Büchner funnel, etc.) dry it, note the yield and measure the melting point.
For purification, recrystallize from ethanol. You should receive red needles with a melting point of $\pu{134 ^\circ C}$.
NOTE: Wear proper protection when handling the azo dye, which is a cancer suspect.
References:
Did you react aniline (or its hydrochloride) with sodium nitrite in the presence of 2-naphthol?
I'm afraid there will not be any table with $R_\mathrm{f}$ values.These values are not only dependent on the compounds and the mobile phases, but also on the stationary phase: e.g. silica, aluminium oxide, etc.Your best option is to use reference samples and measure the $R_\mathrm{f}$ value yourself for the conditions you want to apply or transfer from TLC to column chromatography.
My suggestion is to collect the crude reaction product (Büchner funnel, etc.) dry it, note the yield and measure the melting point.
For purification, recrystallize from ethanol. You should receive red needles with a melting point of $\pu{134 ^\circ C}$.
NOTE: Wear proper protection when handling the azo dye, which is a cancer suspect.
References:
More
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$R_\mathrm{f}$ is sensitive to particular stationary phase, up to having different $R_\mathrm{f}$ on different plates. Traditionally, it is done comparing $R_\mathrm{f}$ of freshly acquired sample and obtained previously in a different manner reference.
However, I agree with Klaus, use melting point of characterisation if possible.
$R_\mathrm{f}$ is sensitive to particular stationary phase, up to having different $R_\mathrm{f}$ on different plates. Traditionally, it is done comparing $R_\mathrm{f}$ of freshly acquired sample and obtained previously in a different manner reference.
However, I agree with Klaus, use melting point of characterisation if possible.
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