Triethyl orthoacrylate

Zirconium ester homoenolates 43 or 44 can be prepared from the triethyl orthoacrylate 42 with the zirconocene complex of but-l-ene 41 (Cp means cyclopentadiene). These resemble the zinc and titanium species we have been discussing but are not derived from cyclopropanes.11... 

Acid Catalyst for Rearrangements. When guaiacol and triethyl orthoacrylate were reacted in refluxing benzene using propionic acid as a catalyst, only 50% of the desired Claisen rear-rangement/ring closure product was obtained, due to esterification of the catalyst. Use of the more hindered pivalic acid furnished the desired product in quantitative yield (eq 1) see also Sato et al. and Dorsey et ah ... 

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