The synthesis and transition temperatures of 5-(4-alkyl- and 4-alkoxy-phenyl)-2-cyanobenzo[b]furans and a 5-(4′-alkylbiphenyl-4-yl)-2-cyanobenzo[b]furan: a comparison with their biphenyl and terphenyl analogues was written by Friedman, Mark R.;Toyne, Kenneth J.;Goodby, John W.;Hird, Michael. And the article was included in Liquid Crystals in 2001.Synthetic Route of C9H5BrO3 This article mentions the following:
The synthesis and transition temperatures of 5-(4-alkyl- and 4-alkoxy-phenyl)-2-cyanobenzo[b]furans and a 5-(4′-alkylbiphenyl-4-yl)-2-cyanobenzo[b]furan are presented. The 2-cyanobenzo[b]furans show similar mesophase types to the analogous biphenyl and terphenyl compounds, which were obtained by replacing the benzo[b]furan unit with a Ph ring. The transition temperatures for the 2-cyanobenzo[b]furan compounds are always higher than for their biphenyl and terphenyl counterparts, but they are much lower than for the corresponding phenylnaphthalenes. Five mesogenic benzo[b]furans without a cyano group were prepared as intermediates and these compounds have lower clearing points than their biphenyl analogs. In the experiment, the researchers used many compounds, for example, 5-Bromobenzofuran-2-carboxylic acid (cas: 10242-11-2Synthetic Route of C9H5BrO3).
5-Bromobenzofuran-2-carboxylic acid (cas: 10242-11-2) belongs to benzofurans derivatives. Benzofurans are only weakly aromatic in nature and they are cleaved by many oxidative and reductive conditions. Substituted benzofurans find applications such as fluorescent sensors, oxidants, in drug discovery, and in another field of chemistry and agriculture.Synthetic Route of C9H5BrO3
Referemce:
Benzofuran – Wikipedia,
Benzofuran | C8H6O – PubChem