Triflimide-catalysed sigmatropic rearrangement of N-allylhydrazones as an example of a traceless bond construction was written by Mundal, Devon A.;Avetta, Christopher T. Jr.;Thomson, Regan J.. And the article was included in Nature Chemistry in 2010.Quality Control of Isopentyltriphenylphosphonium bromide This article mentions the following:
The recognition of structural elements (i.e., retrons) that signal the application of specific chem. transformations is a key cognitive event in the design of synthetic routes to complex mols. Reactions that produce compounds without an easily identifiable retron, by way of either substantial structural rearrangement or loss of the atoms required for the reaction to proceed, are significantly more difficult to apply during retrosynthetic planning, yet allow for non-traditional pathways that may facilitate efficient acquisition of the target mol. A triflimide (Tf2NH)-catalyzed rearrangement of N-allylhydrazones has been developed that allows for the generation of a sigma bond between two unfunctionalized sp3 carbons in such a way that no clear retron for the reaction remains. This new ‘traceless’ bond construction displays a broad substrate profile and should open avenues for synthesizing complex mols. using non-traditional disconnections. In the experiment, the researchers used many compounds, for example, Isopentyltriphenylphosphonium bromide (cas: 28322-40-9Quality Control of Isopentyltriphenylphosphonium bromide).
Isopentyltriphenylphosphonium bromide (cas: 28322-40-9) 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. Commercially available organobromine pharmaceuticals include the vasodilator nicergoline, the sedative brotizolam, the anticancer agent pipobroman, and the antiseptic merbromin. Quality Control of Isopentyltriphenylphosphonium bromide
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary