p-Methoxyphenethyl Methyl Ether-d3 is labelled p-Methoxyphenethyl Methyl Ether (M226400), a reagent used to prepare terminal alkenes via Indium(I)-catalyzed alkyl-allyl coupling of Me ethers with 9-BBN-derived allylborane. It can also be used in the synthesis of hordenine (H669600).