Single Methylenic-bridged Condensation Products

With 2,4-dialkylphenols the condensation with formaldehyde is restricted to formation of the methylene-bridged product. Thus 2-tert-butyl-4-methylphenol 

6-Dialkylphenots are also employed. Thus, 2,6-di-tert-butylphenol with furfural affords a bisphenol with a furfuryl bridge (ref.78), again a compound with antioxidant uses. 

By contrast although alkylphenols do not appear to have been used. It is of interest that an alkylation rather than substitution and acylation products are formed in the reaction of phenol with levulinic acid (ref. 79). Thus in the 

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