The hitherto unknown 6-dimethylaminobenzothiazole-2-carbaldehyde was prepared as a starting compound for the synthesis of novel push-pull benzothiazole derivatives with reverse polarity. These compounds are substituted at the 2-position by strong electron-acceptor groups and at the 6-position by NMe2 as strong electron-donor. The new method for synthesis of 6-dimethylaminobenzothiazole involved the successful use of sonochemical reductive methylation. Expected non-linear optical properties of target molecules were studied by EFISH method.
benzothiazole - non-linear optics - push-pull system - reverse polarity - hyperpolarizability