High Bees!
Last night swim met an old, weird looking man in one of his dreams... the man told me the following:
Into a 2000ml RBF were added 288g of Sodium Acetate, 57,7g of phenylacetic acid and 350g of Acetic Anhydride (all reagents were p.a.).
A reflux condensor and a trying tube were added to the apparatus, and the mixture was refluxed for 20 hours.
Note: At first a heating mantle was used, but this didnt work. The solution was unstirrable because of the enormous masses of NaAc.- so the solution overheated! -> A oil bath at 160°C provided good heating. A lot of the NaAc was just sitting at the walls of the flask.
After 20H about 200ml of Acetic Acid/Acetic Anhydride were distilled of (760mm Hg), and after cooling of the residue 600ml of water were added and the mixture was stirred vigurously. (a lot of heat was generated here, because of the exothermic reaction of the excess anhydride with water.)
After the solution had cooled down (all solids went into solution) 2 layers formed. the top layer was dark red/brown while the bottom (aqueous) layer was only slightly orange.
The whole stuff was extracted with 3x 100ml of DCM. The combined extracts were washed with 5% NaOH-Solution, until the washing solution stayed alkaline (removing excess Acetic Acid and Phenylacetic acid).
The DCM layer was washed once more with water to remove traces of NaOH, dried over sodium sulfate (wash the drying agent with some additional DCM).
The DCM was distilled off and the residue was distilled under vacuum with a 30cm-vigreux column.
At 95°C (14mBar ~10mm Hg) a yellow (maybe a hint of greenish) liquid distilled over. During the distillation the temperature rised to ~120°C (distillate had the same color during the whole distillation progress).
Yeild: 35,4g of P2P (62,3% of theory)
Best wishes,
xicori
PS.: the old man also gave me some photos, so if anybee is interested they could be posted here (if rhodium has some webspace
)
