Novel, highly polarizable thiophene derivatives for use in nonlinear optical applications was written by Seed, Alexander;Cross, Gregory J.;Toyne, Kenneth J.;Goodby, John W.. And the article was included in Liquid Crystals in 2003.COA of Formula: C7H9BrS This article mentions the following:
The synthesis of a variety of thiophene-containing materials for use in electrooptic devices requiring highly birefringent materials is reported. The refractive indexes were measured with the use of an Abbe refractometer, and from these results the optical anisotropies, polarizabilities and order parameters were determined The replacement of a Ph ring by thiophene leads to large enhancements of polarizability. The most significant increases in polarizability anisotropy were observed when the rigid core was a collinear 5,5′-disubstituted-2,2′-dithienyl unit. The changes in the optical properties are discussed in terms of the structural units (thiophene, Ph, isothiocyanate, nitrile, butylsulfanyl, alkoxy,and alkylmoieties) used and their positions with respect to the mol. core. In the experiment, the researchers used many compounds, for example, 2-Bromo-5-propylthiophene (cas: 172319-75-4COA of Formula: C7H9BrS).
2-Bromo-5-propylthiophene (cas: 172319-75-4) belongs to organobromine compounds. Many of the organo bromine compounds are relatively nonpolar. Bromine is more electronegative than carbon (2.8 vs 2.5) and hence the carbon in a carbon–bromine bond is electrophilic in nature. One prominent application of synthetic organobromine compounds is the use of polybrominated diphenyl ethers as fire-retardants, and in fact fire-retardant manufacture is currently the major industrial use of the element bromine.COA of Formula: C7H9BrS
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary