Geminal Diazides Derived from 1,3-Dicarbonyls: A Protocol for Synthesis

Abstract

Geminal diazides constitute a rare class of compounds where only a limited number of methods are available for their synthesis. We present the reaction of 1,3-dicarbonyl compounds (as exemplified by malonates, 3-oxoesters, and 1,3-diketones) with molecular iodine and sodium azide in aqueous DMSO providing a general access to geminal diazides. A broad range of geminal diazides with various structural motifs including sterically demanding substituents and ordinary functional groups were synthesized, and it was shown that the diazidation of 1,3-dicarbonyls can be selectively achieved even in the presence of other 1,3-dicarbonyls with substituents at 2-position. Additionally, several diazides were studied regarding their thermal stability.

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…”

“…Therefore an alternative route with milder reaction conditions was tried for the azido esters [6]. Sodium bicarbonate and iodine was used together with sodium azide in DMSO/H 2 O at room temperature.…”

“…To introduce more azido groups, the geminal diazidation was also carried out from the formerly synthesized azidopropanol esters (5) and (6).…”

“…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].…”

“…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]. In 2015 a direct diazidation with iodine and sodium azide at room temperature was published by Kirsch et al [6]. Yanada suggest a way for synthesis of α,α-diazoketones using N-iodosuccinimide (NIS) and trimethylsilyl azide (TMSN 3 ) [7].…”