Dual C‐13 and deuterium labeled perillic acid, [(1,1‐dideuterio‐1‐13C‐2‐methyl)ethenyl]‐1‐cyclohexene‐1‐carboxylic acid (6) and deuterated perillyl alcohol, [(2,2‐dideuterio‐1‐methyl)ethenyl]‐1‐deuteriohydroxymethyl‐1‐cyclo‐hexene (9) were synthesized from commercially available (4S)‐(‐)‐perillaldehyde (1). Compound 1 was first protected with ethylene glycol to yield the ethylene ketal followed by oxidation with OsO4/NalO4 to cleave the terminal double bond to afford the key intermediate ketone, 4‐acetyl‐1‐cyclohexene‐1‐carboxaldehyde ethylene ketal (3). 3 was then converted to the labeled perillyl aldehyde by Wittig reaction with prepared Ph3P13CD3l or Ph3PCD3l followed by deprotection to give the labeled perillaldehydes, [(2,2‐dideuterio‐2‐13C‐1‐methyl)ethenyl]‐1‐cyclohexene‐1‐carboxaldehyde (5) or [(2,2‐dideuterio‐1‐methyl)ethenyl]‐1‐cyclohexene‐1‐carboxaldehyde (8). 5 was further oxidized by freshly prepared Ag2O to give the desired compound 6. 8 was reduced by LiAlD4 to afford the desired compound 9. The same synthetic procedure may be adopted to synthesize the radioactive isotope labeled perillic acid and perillyl alcohol. © 1997 John Wiley & Sons, Ltd.