(4S,6R)-6-(chloromethyl)-4-[[(4S,6S)-6-[[(4S,6R)-6-(chloromethyl)-4-cyano-2,2-dimethyl-1,3-dioxan-4-yl]methyl]-2,2-dimethyl-1,3-dioxan-4-yl]methyl]-2,2-dimethyl-1,3-dioxane-4-carbonitrile 在
18-冠醚-6 、 potassium iodide 作用下,
以
xylene 为溶剂,
以62%的产率得到(4S,6R)-4-[[(4S,6S)-6-[[(4S,6R)-4-cyano-6-(iodomethyl)-2,2-dimethyl-1,3-dioxan-4-yl]methyl]-2,2-dimethyl-1,3-dioxan-4-yl]methyl]-6-(iodomethyl)-2,2-dimethyl-1,3-dioxane-4-carbonitrile