(5RS,6SR,7SR,10RS)-5-hydroxy-10-methyl-3,4,5,6,7,8-hexahydro-5,6-propano-2H-1-benzopyran-6-propanenitrile 在
2-萘磺酸 作用下,
以
苯 为溶剂,
反应 1.0h,
以31%的产率得到(4aSR,5SR,10bRS,12RS)-12-methyl-4,4a,5,6,9,10-hexahydro-3H,8H,5,10b-propanopyrano<2,3-h>quinolin-2(1H)-one