Cyclotriveratrylene amides

Raston has reported an acid-catalyzed Friedel-Crafts reaction [89] in which compounds such as 3,4-dimethoxyphenylmethanol were cyclized to cyclotriveratrylene (Scheme 5.1-57). The reactions were carried out in tributylhexylammonium bis(tri-fluoromethanesulfonyl)amide [NBu3(QHi3)][(CF3S02)2N] with phosphoric or p-toluenesulfonic acid catalysts. The product was isolated by dissolving the ionic liq-uid/catalyst in methanol and filtering off the cyclotriveratrylene product as white crystals. Evaporation of the methanol allowed the ionic liquid and catalyst to be regenerated. 

A more recent - but much less acidic example - was presented by Raston et al. who converted 3,4-dimethoxyphenylmethanol to cyclotriveratrylene using mixtures of tributylhex-ylammonium bis(trifluoromethanesulfonyl)amide [NBu3(C6H13)][(CF3S02)2N] and phosphoric or p-toluenesulfonic acid (Scheme 3) [47]. 

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