Triphenylmethane dye ethynologues with absorption bands in the near i.r.
Abstract
The first examples of triphenylmethane dye ethynologues (i.e, p-dimethylaminophenylethynylxanthenylium, thioxanthenylium, and selenoxanthenylium perchlorates) absorbing in the near i.r. (up to 802 nm in CH2Cl2) have been synthesized by treatment of the corresponding alcohols with acids.