|Anybody isomerised Allylbenzene with BuOH?||Bookmark|
Has anybody attempted any of these two on allylbenzene with no problems?
To 91 mL (100g, 620 mmol) safrole were added 500 mL of a 3M solution of potassium hydroxide in n-butanol* and the reaction mixture was stirred under reflux for 3 h. After cooling, the mixture was poured into a solution of 3 mL of concentrated hydrochloric acid and 20 mL of ice water. After neutralization, the organic layer was washed with water and dried with anydrous Na2SO4. After removal of the excess n-butanol, the residue obtained was distilled under reduced pressure giving 9.5 g (95%) of pure isosafrole as a colorless oil, with spectra in agreement with the literature. J Braz Chem Soc 11(4), 371-374 (2000)
You distill the BuOH at reduced pressure as well right?There is a table in safrole isomerisation a review on Rhodium's site from Syn. Comm. 27(24), 4335-4340 (1997) that suggests using 4M KOH with Butanol refluxing for 15 minutes to get 99% yield.
I havn't been able to get to these references yet, but they sound tempting. I'm also keen to find out how to stick a condenser through my microwave and isomerise without cooking my face.