Process for the synthesis of benzothiadiazole compounds

摘要

The invention relates to a significantly improved process for the preparation of benzothiadxazole compounds which can be used in the production of Luminescent Solar Concentrators, (LSC). In particular, the synthesis process of the present invention is oriented towards the preparation of 4,-di-2-thienyl-2,1,3-benzo-thiadiazole.

主权项

1. A process for the preparation of compounds having general formula (A): wherein: the two thienyl groups —C4HS(R1)2 are the same, each R1 of the thienyl group is independently selected from H, linear or branched alkyl, cycloalkyl, aryl, alkyl-aryl, alkoxyl, or substituted alkoxyl, each R2 is independently selected from H, linear or branched alkyl, cycloalkyl, aryl, alkyl-aryl, alkoxyl, or substituted alkoxyl, or the adjacent R1 groups of the thienyl group and/or adjacent R2 groups, are bound to each other and, together with the carbon atoms to which they are bound, form a cycle or a polycyclic system, aliphatic or aromatic, or containing one or more heteroatoms, wherein said process comprises reacting, in the presence of a Pd-containing catalyst, at a temperature higher than 120° C. and lower than or equal to 160° C. and in the presence of a solvent selected from dimethylsulfoxide (DMSO) and dimethylformamide (DMF), a compound having formula (B), wherein: X is a halogen selected from Cl, Br and I, each R2 is independently selected from H, linear or branched alkyl, cycloalkyl, aryl, alkyl-aryl, alkoxyl, or substituted alkoxyl, or the adjacent R2 groups are bound to each other and, together with the carbon atoms to which they are bound, form a cycle or a polycyclic system, aliphatic or aromatic, or containing one or more heteroatoms, with a compound having formula (c) wherein: each R1 is independently H, linear or branched alkyl, cycloalkyl, aryl, alkyl-aryl, alkoxyl, or substituted alkoxyl, or the R1 adjacent groups are bound to each other and, together with the carbon atoms to which they are bound, form a cycle or a polycyclic system, aliphatic or aromatic, or containing one or more heteroatoms, and R3 is an alkyl containing from 1 to 6 carbon atoms; wherein: the molar ratio between the compound having formula (C) and the compound having formula (B) is equal to 2; the palladium is used in an amount ranging from 0.01 to 0.1 moles per 100 moles of compound having formula (B); and said process is carried out within a time ranging from 10 to 35 minutes.