35316-47-3Relevant articles and documents
Synthesis of trans-γ-Monocyclofarnesol
Vig, O. P.,Sharma, M. L.,Trehan, Navneet,Verma, N. K.
, p. 450 - 452 (2007/10/02)
The starting material, 2-formyl-6,6,dimethylcyclohexanone (II) in the synthesis of the title compound, is converted into the corresponding 2-isobutoxymethylene-6,6-dimethylcylohexanone (III).Reduction of (III) with LAH followed by treatment with 50percent sulphuric acid gives the α,β-unsaturated aldehyde (IV).LAH reduction of IV yields 1-hydroxymethyl-3,3-dimethylcylohex-1-ene (V) which on mercuric acetate catalysed transetherification with ethyl vinyl ether affords the vinyl ether (VI).Claisen rearragement of VI under an inert atmosphere furnishes 2-(6',6'-dimethyl-2'-methylenecylohexyl)ethanal (VII).Aldehyd VII on Wittig reaction with methoxymethylenetriphenylphosphorane provides the ether (VIII) which is readily converted into the ketal (IX) on treatment with ethylene glycol in the presence of catalytic amount of PTS in dry benzene.Deketalisation of IX with PTS in aq. acetone gives the aldehyde (X) which on Grignard reaction with methylmagnesium iodide furnishes 4-(6',6'-dimethyl-2'-methylenecylohexyl)butan-2-ol (XI).Oxidation of XI with pyridinium chlorochromate in anhydrous methylene chloride yields the ketone (XII) which when subjected to Grignard reaction with vinylmagnesium bromide in dry THF provides the vinylic alcohol (XIII).Treatment of XIII with acetic anhydride and glacical acetic acid in the presence of PTS furnishes the allylic acetate (XIV) which on refluxing with methanolic potassium hydroxide in the presence of a little water gives trans-γ-monocyclofarnesol (I).
