FeCl3-catalyzed Synthesis of Dehydrodiisoeugenol

Dehydrodiisoeugenol (DDIE) synthesis has been performed by modifying a method recommended by Leopold with a different ratio of isoeugenol and FeCl₃ (1.9:1). FeCl₃ was chosen as catalyst due to its efficiency and environment-friendly property. This modification yielded 22.93 % of product. The product, a white crystalline form, was characterized using thin layer chromatography, melting point, UV, IR, HRMS, and NMR spectroscopy, as well as HPLC, employing pure DDIE as the standard. TLC chromatogram showed Rf 0.32 using n-hexane/ethyl acetate (8:2). The crystals melted at 138-139 ^oC, while its UV maximum was detected at l 273 nm. IR spectrum showed a specific broad O-H stretch at 3437.15 cm^-1, C-H aromatic and C-H alkene at 3163.26 and 3024.38 cm^-1, C-H alkyl stretch at 2951.09 and 2927.94 cm^-1. An overtone peak of aromatic was detected at 2100 to 1700 cm^-1. C-O peak was detected at 1126.43 cm^-1. HPLC showed that this compound was eluted at 11.886 minutes after it was injected to a C18 column 250 x 4 mm using a mixture of methanol and double distilled water (73:27) for mobile phase. HRMS spectra predicted that the molecular structure is C₂₀H₂₂O₄ as showed by abundance peak at <em>m/z </em>327.1595 of [M+H]⁺. ¹H-NMR and ¹³C-NMR indicated that the synthesized compound contains 13 types of proton and 20 types of carbon. Herein we reported that white needle-like crystals of DDIE using FeCl₃ as catalyst had been synthesized, moreover the decreasing of the catalyst reduced the yield of the product.