01-30-04 22:36
No 485563
it is known that in the effecient bio-synth of L-PAC the addition of ethanal (acetaldehyde) improves yield, and that benzaldehyde is needed.
an effecient way to obtain both of these would seem to be to inact a reverse aldol condensation on cinnamaldehyde, TFSE did not return any hits on "benzaldehyde cinnamaldehyde reverse aldol".
could someone comment on the reaction conditions needed to cause cinnamaldehyde to undergo a reverse aldol, and capture both products.
refluxing an alkaline tincture would seem obvious but would the volatile ethanal be lost? or would any side reactions occur?
(Newbee)
01-31-04 08:36
No 485653
"Into a three neck flask equipped with stirrer, thermometer and reflux condenser is placed 10 grams of cassia oil and 100 ml of a 3% aqueous sodium carbonate solution. Boiling chips are added and a water-washed stream of nitrogen is passed over the reaction mass to help prevent oxidation of the formed benzaldehyde. The mixture is heated to reflux and refluxed for a period of 7 hours (100 DEG C.). The resulting material contains 70% benzaldehyde and 30% cinnamaldehyde"
Patent US4617419
There are simular patents which describe adding an emulsifier.
Also others describe higher yield of benzaldehyde/acetaldehyde with only trace amounts of cinnamaldehyde.Same concept..
Ill look em up.
(Hive Bee)
01-31-04 21:33
No 485721
thanks BOS,
30% is alot of left over cinn-hyde, maybe using a bit more alkaline or a stronger alkaline would help, i also wonder what % of ethanal is recovered.
i suppose a alkaline detergent like Na3PO4(TSP) could play both the role of an emulsifier and base.