O Eugenol

Figure 9.3b Conductivity/time curves (a) of cements, showing maxima. Prepared from ZnO ignited at 600 C with A-.-A dry eugenol 0...0 eugenol + 1% water O-.-O eugenol + 1% chloracetic acid ... eugenol+1% acetic acid ... eugenol+1% acetic acid+1% water. Cement powder/liquid ratio = 2-5 g cm (Crisp, Ambersley Wilson, 1980).

B. o-Eugenol. The allyl ether (70 g.) is cautiously (Note 3) brought to boiling in a 500-ml. round-bottomed flask, refluxed for 1 hour, and cooled. The oil is dissolved in 100 ml. of ether (Note 4), and the solution is extracted with three 100-ml. portions of 10% sodium hydroxide. The combined alkaline extracts are then acidified with 100 ml. of concentrated hydrochloric acid diluted... 

When this crude guaiacol allyl ether was rearranged without prior distillation, the yields of o-eugenol were about 10% lower than those obtained with the distilled ether. 

Suggest a method for the synthesis of o-eugenol from o-methoxyphenol ... 

Late-stage ligand-accelerated inter-molecular oleflnation via Pd-mediated C—H activation was utilized toward the convergent construction of the biologically relevant aromatic natural product (+)-lithospermic acid (58) (Scheme 3.34). Subsequent functionalization completed the natural product in efficient 12 steps for the longest linear sequence in 11% overall yield from commercially available o-eugenol. 

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