Calixarenes - essential supramolecular synthons

Sulphuric acid (70%) [CORROSIVE] Aqueous formaldehyde (37%) [TOXIC] Ethanol [FLAMMABLE] 

Note Work wherever possible in a fume hood. 

Round-bottomed flask (150 mL) Syringe (20 mL) and septum Magnetic stirrer and stirrer bar Heat gun Ice bath 

Calixarenes have been synthesized, knowingly or unknowingly, since the 1870s [1], with a specific interest arising in the 1940s [2], yet reproducible syntheses and unequivocal structural assignments have only appeared since the 1980s [3,4], The supramolecular and biomimetic behaviour of this class of macrocycles also has a 

No synthesis for this compound is included simply because different-sized calixarenes and many of their derivatives are now readily available from standard suppliers of fine chemicals at very reasonable prices. Given the cost of the diphenyl ether used in their synthesis, it is generally preferable to buy the 4-f-butylcalix[n]arenes unless they are required on an industrial scale. 

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