Sciencemadness Discussion Board

heptanol straightforward synthesis

blueberry58 - 18-11-2014 at 10:19


Hydrogenation of heptaldehyde requires a complex equipment

The process using pentane and ethylene oxide had been hard to found.

What another simpler process to produce heptanol is available?

Magpie - 18-11-2014 at 10:35

Obtaining primary alcohols can be a challenge IMO. Heptane is readily available at craft stores. I wonder how hard it would be to chlorinate (or brominate) it by free radical halogenation using UV light to form a heptyl halide. Then one could make the alcohol by hydrolysis. I haven't done this - it's just speculation on my part.

[Edited on 18-11-2014 by Magpie]

DraconicAcid - 18-11-2014 at 10:46

Quote: Originally posted by Magpie  
Obtaining primary alcohols can be a challenge IMO. Heptane is readily available at craft stores. I wonder how hard it would be to chlorinate (or brominate) it by free radical halogenation using UV light to form a heptyl halide. Then one could make the alcohol by hydrolysis. I haven't done this - it's just speculation on my part.

[Edited on 18-11-2014 by Magpie]


Halogenating heptane (even assuming that it's all n-heptane and not a mixture of isomers with an average of seven carbons each) is not going to result in 1-haloheptane, but 2-, 3-, and 4-haloheptane (the formation of the primary haloalkane is disfavoured).

Chemosynthesis - 18-11-2014 at 11:43

Hi. You should probably be posting this in Reagents and Acquisition as Organic Chemistry is supposed to have a reference included for your work, and you are requesting a procedure for a reagent.

Since you appear to work in a medical lab (due to your various postings about needing to make reagents for various work-related endeavors, despite not being a chemist but an MD), you should just purchase n-heptanol. Halogenating would also be difficult to stop at mono-halogenated products. What exactly are you up to that you wouldn't purchase this? More selenium experimental therapies? You should really take my advice and consult a colleague in chemistry, which have been abundant in the medical facilities I have worked in, for any sanctioned work. They can provide advice, equipment and safety gear.

The below procedure does not require specialized apparati, despite what you have been led to believe:
Organic Syntheses, Coll. Vol. 1, p.304 (1941); Vol. 6, p.52 (1926)
Fairly simple stirring iron/acetic acid reduction, steam distillation, etc. I had the procedure, but it makes my post impossible to read, so I cut it out and left a citation.

Additionally, you can use the analogous procedure for heptanol by substituting n-halopentanol for the halobutanol in Organic Syntheses, Coll. Vol. 1, p.304 (1941); Vol. 6, p.54 (1926). Check MSDS before attempting any procedures.

[Edited on 18-11-2014 by Chemosynthesis]

blueberry58 - 18-11-2014 at 16:48

I mistook the reduction of alkenes to primary alcohols, which requires high pressures.

Starting from heptaldehyde its interesting but is not practical for me because both products equally not so easy to find and their price is similar. Perhaps is better to buy heptanol.

Thank you Chemosynthesis.

chemrox - 18-11-2014 at 18:01

Since you have the articles why not post them and save some bandwidth at OrgSyn.org?