Hello,
Greetings from Tikrit, where the life of a Gringo is cheaper than Iraqi oil! As I see, one of our colleagues has problems in fighting the War on Drugs.
How long before addition should one prepare the performic solution, and how long should the total addition take?Performic acid is an unstable compound and should always be prepared fresh prior to use. As a rule of the thumb, you can combine your formic acid and hydrogen peroxide solution (slowly and with stirring) and allow it to stand 15-30 min. Then it is ready for use. If you wait longer, you can notice the decomposition of performic acid (gas bells). This does not mean your mixture contains no more performic acid though. Your performic acid mixture is an equilibrium state.
The glycol, what color will it be?If I remember correctly, the colour of
pure glycol will be yellow. However,
orange is a valid colour for the worked-up reaction mixture
.
Is the black H2SO4 ok? and
Upon addition of H2SO4, should the glycol turn that dark purple the same way safrole or isosafrole does? or is this a sign of an incompleted performic?If you boil the performic reaction mixture product in MeOH/sulfuric acid, you will obtain a black oil. If you boil safrole or isosafrole in MeOH/sulfuric acid, I think you will have polymerisation (anyone to confirm?). One black oil is not the same as the other black oil
. You will have to distill the ketone, but if you increase the temp a bit more, you can recover some unreacted glycol. By measuring the amount of unreacted product, you can see if your reaction was (nearly) finished or not. If you follow the guidelines on Rhodium's page, there shouldn't be too many problems though.