SYNTHESIS OF OPTICALLY-ACTIVE APORPHINE AND MORPHINANDIENONE ALKALOIDS VIA P-QUINOL ESTERS

Lead tetraacetate oxidation of N-trifluoroacetylnorcodamine (5) in (S) -(+)-2-phenylpropionic acid gave a diastereomeric mixture of two p-qui nol acylates, which were easily separated to enantiomerically pure 6a and 6b. Treatment of the chiral quinol acylates (6a) and (6b) with tri fluoroacetic acid in CH2Cl2 at room temperature afforded (1R)-(-)-6-tr ifluoroacetylwilsonirine (7a) and (1S)-(+)-(7b), respectively. Saponif ication of 7a and 7b gave rise to (-)-wilsonirine (8a) and its enantio mer (8b), respectively. Similarly, (-)-nordomesticine (12a) and (+)-(1 2b) were synthesized in enantiomerically pure form from 10a and 10b. O n the other hand, acid treatment of 6a and 6b in CH3CN at lower temper ature (-30 degrees C) followed by N-deprotection gave the correspondin g normorphinandienones (15a and 15b) as major products, which were tra nsformed to enantiomerically pure (-)-16a and (+)-sebiferine (16b). In a similar sequence of reactions, (+)-amurine (19a) and its enantiomer (19b) were synthesized.