| Popis: |
Methods for distinguishing among the isomeric 1-, 3- and 7-methoxycycloheptatrienes are reported. Treatment with anisaldehyde in strong perchloric acid produced a blue solution for the first two compounds only (with detection limits of the order of 2 μg), while irradiation ar 256 nm prior to treatment gave magenta solutions for the first and third compounds only. Absorbance was linear with respect to concentration, at least in the range 0.5–8 μg m−1. Both the 1- and 3-isomers were oxidized by cerium(IV) to tropylium salts while the 7-isomer was resistant to attack. Similarly, the 7-isomer did not react with sodium tetrachloropalladate(II) on filter paper while the other two compounds gave black spots. |
