Cal, Dariusz published the artcileA convenient synthesis of ω-hydrazinoalkylphosphonic acids, Recommanded Product: Diethyl (bromomethyl)phosphonate, the publication is Tetrahedron Letters (2016), 57(1), 126-128, database is CAplus.
A simple, efficient, and cost effective method has been developed for the synthesis of ω-hydrazinoalkylphosphonic acids via the nucleophilic substitution reaction of di-Et ω-haloalkylphosphonates and hydrazine using mild reaction conditions, followed by hydrolysis with hydrochloric acid.
Tetrahedron Letters published new progress about 66197-72-6. 66197-72-6 belongs to bromides-buliding-blocks, auxiliary class Aliphatic Chain, name is Diethyl (bromomethyl)phosphonate, and the molecular formula is C5H12BrO3P, Recommanded Product: Diethyl (bromomethyl)phosphonate.
Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary