Arylbis methanes

Table4 Bronsted acidities of arylbis(trifluoromethanesulfonyl)methane.

Substituent effects for acidities of a series of aryl(trifluoromethylsulfonyl)methanes and arylbis(trifluoromethylsulfonyl)-methanes have been analysed successfully in terms of the Yukawa-Tsuno equation using substituent parameters in the gas phase. The resultant resonance demand parameter r value decreased linearly with increasing acidity of the gas-phase acidity values of the unsubstituted parent carbon acids, and the change of the r value was found to be related to the geometric parameters and natural charges of the conjugate carbanions calculated at B3LYP/6-31 lq-G(d,p). 

Various arylbis(triflyl)methanes and various 1,1-bis(triflyl)alkanes have been synthesized from commercially available benzylic halides and 1-alkanols. And Yamamoto and his colleagues designed several dibasic acids by para substitution with diols and aryldilithiums (Figure 2.4) [15]. 

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