Synthesis of 13C‐labelled cutin and suberin monomeric dicarboxylic acids of the general formula HO213C‐(CH2)n‐13CO2H (n = 10, 12, 14, 16, 18, 20, 22, 24, 26, 28)

¹³C‐labeled dicarboxylic acids HO₂¹³C‐(CH₂)_n‐¹³CO₂H (n = 10, 12, 14, 16, 18, 20, 22, 24, 26, 28) have been synthesized as internal standards for LC‐MS and GC‐MS analysis of cutin and suberin monomer degradation by soil‐based microorganisms. Different synthetic strategies had to be applied depending on the chain length of the respective synthetic target and because of economic considerations. ¹³C‐labels were introduced by nucleophilic substitution of a suitable leaving group with labelled potassium cyanide and subsequent hydrolysis of the nitriles to produce the corresponding dicarboxylic acids. All new compounds are characterized by GC/MS, IR, and NMR methods as well as by elemental analysis.