OsO4NaIO4氧化合成醛

OsO4/NaIO4被稱為Lemieux-Johnson試劑,此反應也被稱為Lemieux-Johnson氧化。

與臭氧化法相比,

OsO4/NaIO4

是一種溫和的

烯烴氧化開裂法,在天然產物合成中很有用。烯烴先與

OsO4

反應生成鋨酸酯,再用過碘酸鈉氧化,發生開裂,在生成羰基化合物的同時,

OsO4

再生,所以

OsO4

用催化量即可。當生成的醛易於分子內縮合時,反應最好在兩相系統中進行。

OsO4NaIO4氧化合成醛

To asolution of

1

(1。8 mg) in THF(1 mL) was added

OsO4

(excess) and then a solutionof NaIO4, (excess) in H2O (1 mL)。 After a period of 1 hr,H2O (5 mL) was added andthe aq。 solution was extracted with three 5ml portions of CHCl3。 Thecombined CHCl3 layers were dried over Na2SO4,and concentrated to give a residue, which was separated by preparation TLC (SiO2,5% MeOH-CHCl3)。 Compounds

2

and

3

wereobtained。

Tetrahedron,

41; 6; 1985;1007-1018

Criegee臭氧化反應