Abstract: Taking advantage of the selectively crystalline specialty of 2-amino-2-methyl-1-propanol toward isopimaric acid, butanolidine isopimarate (2-amino-2-methyl-1-propanol isopimaric acid salt) was prepared by reacting 2-amino-2-methyl-1-propanol with thermally isomerized slash pine rosin that was freshly prepared from oleoresin or rosin, then purified by multi-recrystallization. Thereafter, isopimaric acid was isolated from the butanolidine isopimarate by acidic decomposition in a yield of 10.1% based on the rosin, with purity of 95.4% isopimaric acid. The isolation yield of isopimaric acid is 42.2% based on its content in rosin.

Key words: slash pine oleoresin, slash pine rosin, isopimaric acid, butanolidine isopimarate, multi-recrystallization