Cyclophane tetraanion

A tetraanion salt (84 )/4M has been formed by stepwise four-electron transfer from 4,7,12,15-tetrastyryl[2.2]paracyclophane (8) to lithium, sodium, and potassium metals in [2Hx]THF at 220 K a strong effect of the cyclophane hub on the charge distribution has been demonstrated and the influence of o1, o2, o3, o4-tetramethyl and px, p2,pi,pA-tetramethoxy substituents on the ease of reduction has been tested.9... 

The first alkali metal reduction study of cyclophanes was conducted by Mullen, who reduced 21 with Li [99]. Two anions were observed in the NMR spectra a dianion and a tetraanion. The chemical shifts of both these anions showed that a peripheral conjugation is present. The reduction drastically slowed down the rotation... 

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