hello, bees!
first of all thanks to chromic for working out a viable peracetic procedure:
Post 250788
(Chromic: "Peracetic in DCM - dreams of success", Methods Discourse).
the goal was to make the epoxide of anethole as opposed to the glycol / acetyl ester.
the procedure tried was chromic's (100 mmol anethole) with an 0.5 molar amount
of Na2CO3 (1/2 mol Na2CO3 per mol CH3COOH) instead of NaAc and TCE instead of DCM. some
mishaps occured. yield was very very low and it isn't granted that the epoxide was formed.
to make a long story short: about 2/3rd of the Na2CO3 was added to the peracetic acid
(which had to be slightly diluted with water), the other part was dissolved in some water
and directly added to the TCE in which the reaction was performed. in the beginning
the reaction was cooled on ice bath, but not noticing any exothermic reaction, it was
stirred for 8h at rt. pH was 7 throughout the reaction. after distillation, ended up
with 9.5g anethole and 2.0g of a dark yellow, viscous residue smelling like PMP2P which was
not further distilled.
i see many reasons why this reaction may not work. the most convincing ones:
* the chemist is unable.
* with a pH around seven, most of the peracetic is dissociated and stays in the aqueous layer.
ideas:
* heat the reaction
* let it run longer
* don't add water
* use MeOH or EtOH like in oxone procedure
suggestions very welcome!
(usually this would not be post worthy, but i'll be away for some weeks, so i thought
post it, so other bees trying this can learn from it.)
couch terrorist