Azides fragmentation

The bond lengths for the azide MN3 fragment cover a wide range, as shown in Table 20, and are of a similar range to the organic azide fragments. The mean bond lengths are not... 

There have been several papers on Ag oxalate— Ag2C204- Macdonald and Hinshelwood (Ref 7) confirmed the Berthelot equation, according to which the only products of decompn of Ag oxalate are metallic Ag and C02. Benton and Cunningham (Ref 9) found that the rate of thermal decompn of Ag oxalate may be increased by previously exposing it to ultraviolet radiation. During the thermal decompn of Ag oxalate, fragments of metallic Ag are formed. This has been confirmed by conductivity measurements (Ref 10) or by X-ray examination (Ref 11). Tompkins (Ref 1.2) investigated the thermal decompn of Ag oxalate at 110—130°. Its decompn, in his opinion, is similar to that of Ba azide... 

The spin label in question may as well be in the carboxylic acid fragment as in the alcohol moiety. Photoreactive esters bear azido groups in their carboxylic acid moieties. The esterification of nitroxide- or azide-bearing carboxylic acids with complex alcohols and CDI is illustrated in Table 3-6 by way of some examples. 

Aryldioxophosphoranes such as aryl- and alkyl-iminooxophosphoranes number among the short-lived metaphosphonates. The former are best obtained by fragmentation of cyclic phosphinic esters, and the latter by rearrangement of aryl- and alkyl-substituted phosphoryl azides and nitrenes, respectively. This reaction is reminiscent of the phosphorylcarbene/methyleneoxophosphorane rearrangement discussed in Section 2. 

The nonsymmetrical quinolizidine 373 was obtained from the acyclic symmetrical precursor 372 by means of a reaction sequence comprising azide formation, intramolecular 1,3-dipolar cycloaddition, thermal triazoline fragmentation to a diazoalkane, and Michael addition individual steps, as shown in Scheme 85 <2005CC4661>. 

In remembrance of the isolation of carbene 78 (Section m.C) it seems acceptable that 141, formed from 140 by a [l,2]-migration of the substituent, functions as a second intermediate. Carbene 141 can subsequently fragment into a nitrene 143 and carbon monoxide or open to an isocyanate 144, which alternatively may also be generated from an acid azide via acylnitrene 142. In comparison to calculated reaction pathways 75 78 and 82 81 (Schemes... 

Gaseous fragments are eliminated on heating, and numerous chemical species are formed at the reacting surface of the azide polymer. The heat transfer process from the high-temperature zone to the reacting surface determines the burning rate of an azide polymer. 

As described in Sections 4.2.4.1 and 5.2.2, GAP is a unique energetic material that burns very rapidly without any oxidation reaction. When the azide bond is cleaved to produce nitrogen gas, a significant amount of heat is released by the thermal decomposition. Glycidyl azide prepolymer is polymerized with HMDI to form GAP copolymer, which is crosslinked with TMP. The physicochemical properties of the GAP pyrolants used in VFDR are shown in Table 15.3.PI The major fuel components are H2, GO, and G(g), which are combustible fragments when mixed with air in the ramburner. The remaining products consist mainly of Nj with minor amounts of GOj and HjO. 

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