Gutmann, Bernhard published the artcileSafe generation and synthetic utilization of hydrazoic acid in a continuous flow reactor, Safety of 5-(4-(Trifluoromethyl)phenyl)-1H-tetrazole, the publication is Journal of Flow Chemistry (2012), 8-19, database is CAplus.
Hydrazoic acid (HN3) was used in a safe and reliable way for the synthesis of 5-substituted-1H-tetrazoles and for the preparation of N-(2-azidoethyl)acylamides in a continuous flow format. Hydrazoic acid was generated in situ either from an aqueous feed of sodium azide upon mixing with acetic acid, or from neat trimethylsilyl azide upon mixing with methanol. For both processes, subsequent reaction of the in situ generated hydrazoic acid with either organic nitriles (tetrazole formation) or 2-oxazolines (ring opening to β-azido-carboxamides) was performed in a coil reactor in an elevated temperature/pressure regime. Despite the explosive properties of HN3, the reactions could be performed safely at very high temperatures to yield the desired products in short reaction times and in excellent product yields. The scalability of both protocols was demonstrated for selected examples. Employing a com. available bench top flow reactor, productivities of 18.9 g/h of 5-phenyltetrazole and 23.0 g/h of N-(1-azido-2-methylpropan-2-yl)acetamide were achieved.
Journal of Flow Chemistry published new progress about 2251-79-8. 2251-79-8 belongs to isoxazole, auxiliary class Trifluoromethyl,Fluoride,Benzene, name is 5-(4-(Trifluoromethyl)phenyl)-1H-tetrazole, and the molecular formula is C8H5F3N4, Safety of 5-(4-(Trifluoromethyl)phenyl)-1H-tetrazole.
Referemce:
https://en.wikipedia.org/wiki/Isoxazole,
Isoxazole | C3H3NO – PubChem