16737-04-5Relevant articles and documents
Cyclisation de composes acetyliniques carbonyles via leur ether d'enol silyle: II. Synthese et reactivite de quelques ethers d'enols derivees d'aldehydes ou de cetones acetyleniques terminaux
Boaventura, Maria-Amelia,Drouin, Jacques
, p. 1015 - 1026 (2007/10/02)
A number of silyl enol ethers of ω-acetylenic ketones or aldehydes have been prepared following various literature procedures which are compared to each other.By treatment with mercury (II) chloride (1.1 equiv.) in the presence of HMDS (0.2 or 1.5 equiv.) at room temperature, followed by acidification with aqueous HCl-NaI, silyl enol ethers 1, 2, 3, 9, 11, 12 and 13 are cyclized in high yield into 2-alkylidene-1-oxocyclopentanes, methylene- spiro or poly-cyclanones, a methylene cyclopentane unit being formed in the reaction.In the same way, from silyl enol ethers 4, 8 and 10 a methylenecyclohexane unit is formed.In all the products the exocyclic position of the C=C double bond so formed is fully maintained.