The Synthesis of α‐Azidoesters and Geminal Triazides

Abstract

Three simple methods for the synthesis of geminal triazides are described: Starting from 1) 3-oxocarboxylic acids, 2) iodomethyl ketones, or 3) terminal olefins, a range of triazidomethyl ketones can be constructed under mild oxidative reaction conditions by the use of IBX-SO3 K, a sulfonylated derivative of 2-iodoxybenzoic acid (IBX), and NaN3 as an azide source. This is the first report of representatives of this novel class of triazide compounds: Despite their high nitrogen content, the geminal triazides are easy to handle, even when preparative-scale syntheses are performed. (Caution: These procedures still require protective measures!) The triazides are now broadly available for further studies regarding their properties and reactivity. Furthermore, we show how the method can be used to provide α-azidoesters, which are potential building blocks for amino acids.

Synthesis and Characterization of New Azido Esters Derived from Malonic Acid

“…These properties could fit the requirements for suitable additives in propellant formulations. (4) > 360 N > 40 J insensitive b-1,3-DAPM (5) 160 N 35 J sensitive b-2,3-DAPM (6) 160 N 35 J sensitive DA-bAEM (7) 36 N 1 J very sensitive DA-b-2,3-DAPM (8) 36 N < 1 J very sensitive DA-b-1,3-DAPM (9) 36 N < 1 J very sensitive…”

“…The physicochemical and energetic properties of the three new geminal diazidated azido malonic acid esters are shown in Table 1. They were compared to the synthesized precursor azido esters (4)(5)(6). The energetic parameters like heat of combustion, detonation pressure, detonation velocity and volume of gaseous products were calculated using version 6.03 of Explo5 [13].…”

“…However recent methods use oxidative conditions. The diazidation reaction on the α-position was described by Kirsch et al in 2012 and 2014 with a route involving IBX-SO 3 K as a mild oxidant, sodium azide and catalytic amount of iodine [4]. On the other hand Kamble et al investigated a synthesis with sodium periodate and sodium azide as reagent system for diazidation of aryl ketones [5].…”

“…The solution as then dried over MgSO4 and the solvent was removed in vacuo, to yield the product (0.31 g, 0.72 mmol, 51 %) as yellowish oil. 1 H NMR (400 MHz, CDCl 3 , ppm): δ = 4.48-4.35 (m, 4H), 3.88-3.83 (m, 2H), 3.52-3.44 (m, 4H).…”

Synthesis of geminal bis- and tristriazoles: exploration of unconventional azide chemistry

“…‡ 7 A variant of this procedure also led to the synthesis of geminal triazides, highly energetic compounds that must be handled with caution. 8 In the course of those projects, we realized that the di-and triazides can be converted into their corresponding geminal bis-and tristriazoles using cycloaddition reactions with alkynes. 9 Besides our own reports, the two compound classes turned out to be somewhat neglected, and most previous reports on geminal bistriazoles focused on geminal bis(benzotriazol-1-yl)methyl derivatives, as shown, for example, in the detailed studies by 11 Even more surprising, our review of the literature revealed only one example for a geminal tristriazole, i.e.…”