D-Homo rearrangement of steroids

What is D-Homo rearrangement of steroids?

The D-Homo rearrangement of steroids was first discovered in 17β-hydroxy-20-ketosteroids, but it has since been extensively investigated in the 17α-hydroxy-20-keto series. This chemical reaction involves an acyloin rearrangement that is catalyzed by either an acid or a base, and it results in the formation of a six-membered D-ring without the loss of any carbon atoms.

D-Homo rearrangement of steroids
D-Homo rearrangement of steroids

When 17-hydroxy-20 derivatives of steroids are treated with bases or acids (including Lewis acids), they undergo D-homo rearrangement, leading to the formation of six-membered D-rings. This reaction can also occur in the absence of a carbonyl group, as long as a carbocation is formed at position 20.

The D-homo rearrangement is highly valuable in the preparation of various steroid derivatives due to its versatility and efficiency.


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