Synthesis and corrosion inhibition phenomenon of benzophenothiazine derivatives with aluminium in acidic media

Kumar Swarnkar Pawan, Kumar Su

Abstract

2-Amino-6-substituted benzothiazoles (ASB) on diazotization afford 6- substituted benzothiazolyl-2-diazoniumchlorides (SBDC).Reaction of SBDC with cold solution of â-naphthol in dilute NaOH furnishes á-(2-diazo-6- substituted benzothiazolyl)- â-sodionaphthoxides (DSBS) which on acidification with concentrated HCl gives á-(2-diazo-6-substituted benzothiazolyl)- â-naphthols (DSBN). Reaction ofDSBN with p-substituted anilines gives á-(2-diazo-6-substituted benzothiazolyl)- â-(p-substituted aniline) naphthalenes (DSBSAN). Fusion of DSBSAN with sulphur in presence of iodine results in á-(2-diazo-6-substituted benzothiazolyl)-6- substituted [2,3-b] benzophenothiazines (DSBSB).