FriendlyFinger (Hive Bee)
04-27-03 07:52
No 429703
      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.