Lossen rearrangement

The Lossen rearrangement is the chemical reaction of a hydroxamic acid 1 with a dehydration agent (such as tosyl chloride) to form the O-derivative 2, which spontaneously rearranges to form an isocyanate 3.^[1][2]

The Lossen rearrangement

Several reviews have been published.^[3][4][5]

Hydroxamic acids are commonly synthesized from their corresponding esters.^[6]

References

1. ^  Lossen, W. Ann. 1872, 161, 347.
2. ^  Lossen, W. Ann. 1874, 175, 271 & 313.
3. ^  Yale, H. L. Chem. Rev. 1943, 33, 209. (Review)
4. ^  Bauer, L.; Exner, O. Angew. Chem. Int. Ed. Engl. 1974, 13, 376. (Review)
5. ^  Shiori, T. Comp. Org. Syn. 1991, 6, 821-825. (Review)
6. ^  Hauser, C. R.; Renfrow, Jr., W. B. Organic Syntheses, Coll. Vol. 2, p.67 (1943); Vol. 19, p.15 (1939). (Article)

See also

• Curtius rearrangement
• Hofmann rearrangement
• Schmidt reactionTemplate:Reaction-stub