Cationic Dyes with Sulfur or Phosphorus as Charge-Carrying Atoms

5 Cationic Dyes with Sulfur or Phosphorus as Charge-Carrying Atoms 

When dyes containing anionically displaceable groups are reacted with thioethers, cationic dyes (e g., 54) are obtained in which the sulfonium moiety carries the charge [149], 

By treating dyes that contain a chloroethyl group with thiourea, the cationic charge may be introduced in the form of an isothiouronium residue (e.g., 55) [150], 

To introduce phosphorus as the charge-canying moiety, dyes that contain haloalkyl groups are treated with phosphines such as dimethylphenylphosphine (e.g., 56) [151]. 

---