| 摘要 |
2-Methyl-4,4a-dihydro-3H-carbazolium salts that are useful as dye precursors and dyes derived from those precursors are disclosed. The salts are described by the formula <IMAGE> wherein R1 represents an alkyl, aryl, sulfoalkyl, carboxyalkyl, sulfatoalkyl, alkoxyalkyl, acyloxyalkyl, dialkylarinoalkylene, cycloaminoalkylene, acyl, or alkenyl group having from 1 to 18 carbon atoms; R2 represents an alkyl group having up to 18 carbon atoms; R3 represents hydrogen or an alkyl group having from 1 to 18 carbon atoms; R4 represents hydrogen or an alkyl group having from 1 to 18 carbon atoms; R5 represents hydrogen, nitro, carboxyl, sulfo, hydroxy, halogen, phospho, or an alkoxy, thioalkoxy, oxyalkyl, acyl, alkyl, aryl, or amino group having up to 18 carbon atoms; wherein any two groups R5, or R4 and a group R5, or R1 and R4 may together form a substituted or unsubstituted aryl, heteroaryl, aliphatic, or heteroaliphatic ring; X represents an anion; and a and b represent positive integers such that a equals b. The salts have a partially saturated ring system that rigidifies the chromophore in the precursor and in dyes derived from it. The rigidified chromophores have narrowed absorption bands relative to corresponding non-rigid chromophores. Dyes prepared from the dye precursors of the invention typically have good solubility in non-polar solvents.
|
