Iodoetherification of the ()-3-hydroxy-5-alkenoates 4 leads exclusively to the hydroxytetrahydrofurans 5 whereas similar cyclisations of the corresponding ()-isomers [10, 13 and 15] give largely the iodo-tetrahydrofurans [11, 14 and 16].
的Iodoetherification()-3-羟基-5-烯酸酯4根引线专门向hydroxytetrahydrofurans 5而相应的(类似的环化) -异构体[ 10,13和15 ]得到很大程度上是
碘的
四氢呋喃[ 11,14和16 ] 。