Tellurophenes reactivity, quantitative studies

A quantitative study has been made on the effect of a methyl group in the 2-position of five-membered heteroaromatic compounds on the reactivity of position 5 in the formylation and trifluoroacetylation reaction. The order of sensitivity to the activating effect of the substituent is furan > tellurophene >selenophene = thiophene (77AHC(2l)ll9). 

To date, the quantitative studies on tellurophene nucleus reactivity have come exclusively from our laboratory and are devoted to electrophilic substitution, to some side-chain solvolysis reactions, and to carboxylic acid ionization. 

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