Your write up was good and really helpful, but sometimes it's easier to understand the ins and outs of a reaction when I compare various sources that might explain the reaction in a slightly different way. I have a lot of respect for you, your work and this forum as a whole!
Yes, you should use the same volume of THF when compared to ether. I've read that they both be used in most grignard reaction.
When it come to your other question, I sadly can't help you too much since I'm no where near an expert and don't want to tell you anything I'm not 100% sure about...
Yes. THF can replace ether, and is even preferred over ether in a lot of cases, due to it being generally safer to work with.
Another good route to P2P, starting from benzyl chloride would be to convert it to PAA through a Grignard reaction, which has yields of about 75%. Then you just have to...
Die Route über Nitrethan und Piperonal würde ich dir nicht empfehlen, da sowohl Piperonal als auch Nitroethan nicht leicht zu kaufen sind. Und der letzdendlich hergestellte Stoff ist dann auch MDA, und nicht MDMA
Einfacher währen die Syntheserouten die bei Safrol starten, was leicht aus...