Acetic Acid → 5-methylpentadecanoic Acid

Participants

Reaction Steps

See GENERAL PROCEDURE I. Decyl bromide (compound (1), R=CH3(CH2)9—) is converted to its Grignard reagent with magnesium in dry ether (I, Step (a)). To this is added 5-chloro-2-pentanone (Aldrich C6,2660-3) (I, Step (b)). The reaction mixture is worked up with acetic anhydride (I, Step (c)) to form chloroacetate (3). Acetic acid is eliminated by refluxing (3) in a suitable solvent, e.g., benzene (I, Step (d)) yielding a mixture of chloro-olefin isomers (4). (4) is converted to its Grignard reagent following standard practice. (I, Step (e)). The Grignard reagent is treated with carbon dioxide and aqueous acidic workup (I, Step (f)) followed by catalytic hydrogenation (Pd catalyst) to form 5-methylpentadecanoic acid, (5).

Provenance & Evidence