Synthesis of optically pure (-1-and (+)-adenallene 2 and 3 is described. Racemic adenallene (la) was subjected to deamination with adenosine deaminase monitored by HPLC using a Chiralcel CA-1 column to give (-)-ademIlene (2) and (+)-hypoxallene (4). The latter compound was converted to acetate 5. The reaction of 5 with trifluoromethanesulfonic anhydride and pyridine followed by ammonolysis furnished acetate 6 or (+)-adenallene (3 ...