How about +90% yield of iso in less than 4 hours?

[raffike]

So raf's Iron Pentacarbonyl finally arrived and raf thought to give it a try.Please let me know your opionion about this.

Reagents:
*500 grams of safrole distilled from Ocotea Cymbarum
*3 grams of technical +98,5%NaOH
*3 grams of lab grade Fe(CO)5 from Fluka

Procedure:
500 grams of safrole was put in 2 liter round bottom flask that was sitting on a heating mantle.Overhead stirring was applied and 3 grams of NaOH and 3 grams of Fe(CO)5 was added.Started heating.Somewhere at 110 degrees C obvious exotermic reaction kicked in,just like described in Rhodium's isomerization review,and heating was turned off.15 minutes passed and stirring was turned off and flask was allowed to cool down.When flask was cooled,dark organic mixture was washed with 200 mls 20% acetic acid and then with 200 mls water.Some emulsion formed but that cleared up in about and hour and then organic layer was sepped off with 1 liter separatory funnel.Organic mixture was poured to 2 liter flask,attached claisen still head and liebig conderser with vacuum adapter.Recieving flask was 1 liter round bottom.Vacuum applied and started heating.From 114 C to 118 C at 10 mm vacuum only fraction came over which was almost colourless.

Final yield:456 grams which means +90% yield.There were some losses during the washes that will be avoided next time and raf thinks +95% yield isn't hard to obtain.

[raffike]

Of course we have to keep in mind that Fe(CO)5 is very toxic reagent and it's recommended to do the reaction under fume hood or with good ventilation.Pentacarbonyl(25 mls) costed 30$ for raf and price probably goes down as quantity goes up.NaOH costed raf 50 cents a kg.I think this method would be great candidate for large scale manufacture.No need for certain vacuum or constant reflux temps and reaction is very quick with almost quantitative yield.

[Lilienthal]

The Fe(CO)₅ for $30 is that of 99.999% purity. The normal grade one costs only $50 per 250 g!

[raffike]

Today swiraf's uncle came by and wanted to know how Iron pentacarbonyl smelled like.Sniffed from the bottle and almost collapsed,then he was feeling like shit for few minutes.Seems like this stuff is CNS active too,besides it's toxic to kidneys and liver...
Anyway's raf is hydrolysing glycol at the moment.Glycol was made from this batch of isosafrole.I can definitely smell cardamon,will post yields in a moment...

[raffike]

Yield was bad(55 grams of ketone from 230 grams of iso) but this had nothing to do with isosafrole.Just in case raf performed a test on his fresh made iso.50 mls of iso was distilled at atmospheric pressure and nothing came over below 243-244 C.It smells definitely like iso and there's no reason to doubt in it's purity...

[hellman]

I hope you can work out where you went wrong,.
I hope you can get back to us, and find the culprit,.

I feel for you,.

hellman

[raffike]

Raf still got 270 grams of iso from his last batch.He will process it to ketone this week.