Indole-Derived Arynes and Their Diels-Alder Reactivity with Furans was written by Buszek, Keith R.;Luo, Diheng;Kondrashov, Mikhail;Brown, Neil;VanderVelde, David. And the article was included in Organic Letters in 2007.Reference of 615-55-4 This article mentions the following:
Arynes derived from any position of the ubiquitous indole nucleus are unknown. We have now provided the first evidence for the formation and trapping of the 4,5-, 5,6-, and 6,7-indolynes. A series of o-dihalo indoles (Cl, Br, F) were synthesized and reacted under metal-halogen exchange conditions to give Diels-Alder cycloadducts in high yield with furan. The use of an excess of tert-butyllithium resulted in the rearrangement of the initially formed cycloadduct; however, employing only a slight excess of n-butyllithium cleanly gave cycloadducts with furan. In the experiment, the researchers used many compounds, for example, 3,4-Dibromoaniline (cas: 615-55-4Reference of 615-55-4).
3,4-Dibromoaniline (cas: 615-55-4) belongs to organobromine compounds. Bromine is more electronegative than carbon (2.9 vs 2.5). Consequently, the carbon in a carbon–bromine bond is electrophilic, i.e. alkyl bromides are alkylating agents. The principal reactions for organobromides include dehydrobromination, Grignard reactions, reductive coupling, and nucleophilic substitution.Reference of 615-55-4
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary