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Tosylation of long chain secondary alcohol group
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Keith Raymond
Tosylation of long chain secondary alcohol group
You could try deprotonation with a strong non-neucleophilic base at low temperature for a few hours prior to adding the tosyl chloride.
I have had success using stoichiometric KH in dry THF in a dry-ice / acetone bath for 8 hours prior to adding the electrophile and allowing the reaction to return to room temperature. This works for secondary alcohols in the presence of a secondary amine.
You could try deprotonation with a strong non-neucleophilic base at low temperature for a few hours prior to adding the tosyl chloride.
I have had success using stoichiometric KH in dry THF in a dry-ice / acetone bath for 8 hours prior to adding the electrophile and allowing the reaction to return to room temperature. This works for secondary alcohols in the presence of a secondary amine.
What about using some larger more hindered base than KH, (trying to use readily available, cheap and safe reagents where possible) for the deprotonation? I've been looking into pKa/pKb tables for possible reagents, I'd hopefully like to be able to use Et3N in a suitable solvent, to cut down on waste and use fewer solvents, though haven't had enough time to read through things properly yet.
What about using some larger more hindered base than KH, (trying to use readily available, cheap and safe reagents where possible) for the deprotonation? I've been looking into pKa/pKb tables for possible reagents, I'd hopefully like to be able to use Et3N in a suitable solvent, to cut down on waste and use fewer solvents, though haven't had enough time to read through things properly yet.
I have had success using stoichiometric KH in dry THF in a dry-ice / acetone bath for 8 hours prior to adding the electrophile and allowing the reaction to return to room temperature. This works for secondary alcohols in the presence of a secondary amine.
I have had success using stoichiometric KH in dry THF in a dry-ice / acetone bath for 8 hours prior to adding the electrophile and allowing the reaction to return to room temperature. This works for secondary alcohols in the presence of a secondary amine.
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I've been looking into pKa/pKb tables for possible reagents, I'd hopefully like to be able to use Et3N in a suitable solvent, to cut down on waste and use fewer solvents, though haven't had enough time to read through things properly yet.
I've been looking into pKa/pKb tables for possible reagents, I'd hopefully like to be able to use Et3N in a suitable solvent, to cut down on waste and use fewer solvents, though haven't had enough time to read through things properly yet.
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VOTE