Bicyclo(2.2.1)heptan-2-one → 2-Methylbicyclo(2.2.1)heptan-2-ol

Participants

Reaction Steps

Norbornanone (I) is reacted with methylmagnesium iodide to give 2-methyl-2-norbornanol (II). The compound (II) is reacted with acetic acid and a 75% solution of sulfuric acid to give 2-acetoxy-1-methylnorbornane (III) which is then converted into 1-methyl- 2-norbornanol (IV) with lithium-aluminum hydride. Then the compound (IV) is enzymatically resolved according to the method reported by Christian Triantaphylides et al., Tetrahedron Letters, 26(15), 1857 (1985) to give (1S)-1-methyl-2-norbornanol (V). This optically active alcohol (V) is then oxidized with pyridine dichromate complex to give (1S)-1-methyl-2-norbornanone (VI). The compound (VI) is reacted with methyltriphenylphosphonium bromide in the presence of n-butyllithium to give (1S)-2-methylenenorbornane (VII) which is then treated with peracetic acid to give an epoxy compound. This epoxy compound is treated with a boron trifluoride etherate complex to give (1S,2S)-1-methyl-2-norbornyl aldehyde (VIII) which is then reduced with lithium aluminum hydride to give (1S,2S)-1-methyl-2-hydroxymethylnorbornane (IX).

Provenance & Evidence