Azide compounds

Hydroxymethyl phosphines are susceptible to oxidation to form the phosphine oxide derivative. Therefore, avoid excess oxygen, oxidizing agents, or azide compounds, which react with phosphines in the Staudinger reaction (Chapter 17, Section 5). In addition, metallic surfaces can be modified via the phosphine group to result in hydroxymethyl group substitutions. 

There now are available a number of alkyl azide compounds that may be used in click chemistry reactions and the Staudinger ligation processes. It is not recommended, however, to use aryl azide compounds, as these are light sensitive and photoreactive as well as highly susceptible to reduction in the presence of thiols. Unfortunately, at the time of this writing there are fewer choices in aryl phosphine compounds to participate in this reaction, as commercial sources of labeling reagents are limited. 

Figure 18.10 NHS-PEG-azide compounds can be used to modify amine-containing proteins or other molecules for subsequent conjugation using either the click chemistry reaction or Staudinger ligation.

A photosensitive composition, consisting of an aromatic azide compound (4,4 -diazidodi-phenyl methane) and a resin matrix (poly (styrene-co-maleic acid half ester)), has been developed and evaluated as a negative deep UV resist for high resolution KrF excimer laser lithography. Solubility of this resist in aqueous alkaline developer decreases upon exposure to KrF excimer laser irradiation. The alkaline developer removes the unexposed areas of this resist. 

We have found the combination of the azide compound and the styrene resin is well suited for achieving high resolution and high aspect ratio patterns using KrF excimer laser stepper system, because of the absence of swelling-induced pattern deformation during alkaline development and the suitable optical density at 248 nm in terms of sensitivity. 

The photosensitive azide compound was 4,4 -diazidodiphenyl methane (m.p. 44.0 t). The poly(styrene-co-maleic acid half ester) was used as a resin matrix. 

The azide compound was mixed with the styrene resin in the range of 10 to 40 wt%, and dissolved in 2-methoxy-ethyl acetate. 

With solid sodium hydrogencarbonate instead of the azide, compound jy gave as the main product (85%), together with a trace of 42 (14) This recalls a related precedent, namely, jT-elimination of... 

The second contribution by A. Devi, R. Schmid, J. Muller and R. A. Fischer entitled Materials Chemistry of Group 13 Nitrides reviews the organometalHc precursor chemistry of group-III nitride OMCVD. The authors discuss the various efforts undertaken in the past decade to come up with alternative precursors to compete with the classical system of Ga(CH3)3 and NH3 to grow GaN, which is commercially employed in industry. The potential of the rather exotic organometallic azide compounds as precursors for the nitride materials is critically discussed, showing the limitations and prospects of that approach as well as representing one of the few examples of comprehensive studies on... 

Preparation of Organic Azide Compounds by the Reaction of Sodium Azide with Epoxides in Aqueous Solution [60]... 

Radiation Chemistry of Phenolic Resin Containing Epoxy and Azide Compounds... 

From this result on MRS, we expected that a combination of phenolic-resin-based resist and aqueous alkaline developer would lead to etching-type dissolution and non-swelling resist patterns. In this paper, we report on a new non-swelling negative electron beam resist consisting of an epoxy novolac, azide compound and phenolic resin matrix (EAP) and discuss the radiation chemistry of this resist. 

Materials. Epoxy novolac, DEN-431, obtained from Dow Chemical Co. was selected as the epoxy component. A 3,3 -diazidodiphenyl sulfone synthesized in our laboratory (5) was used as the azide compound. Poly(/7-vinyl phenol) obtained from Maruzen Oil Co. was used as the phenolic resin matrix. The coating solvent was cyclohexanone. The developer used in this study was 0.1 N tetramethylammonium hydroxide aqueous solution. 

The gel permeation chromatograms of MRS are shown in Figure 9, where peaks 1 and 2 represent the azide compound and the main component of poly(p-vinyl phenol), respectively. Peak 3 corresponds to a primary amine, which is one of the exposure-induced reaction products from the azide compound (14). Peak 4 indicates the same exposure-induced high molecular weight components as for EP. 

The result obtained from EAP is shown in Figure 10, where peak 1 represents the azide compound and epoxy novolac dimer, and peaks 2, 3, and 4 represent epoxy novolac trimer, tetramer, and the main component of poly(p-... 

So far only terminal N-bonding of the azide ligand has been reported for Co azide com-plexes.218,273,280 In the case of the Rh azide compounds both terminal274,275 (see 97) and 1,1-/ bonding276 have been found. 

Titanium nitride films have usually been prepared by OMCVD from dialkylamido titanium compounds Ti(NR2)4 and ammonia, which plays a major role in the process as a reducing agent and source of nitrogen.12,13 Other authors have reported the use of azide compounds such as Cp2Ti(N3)2 or [Ti(NMe2)(N3)(p-NMe2)]3(p3-NH), with the former compound,14 contamination of the films by free carbon from the decomposition of the Cp group is mentioned, while with the latter,15 which occurs as a trimeric species, a lack of sufficient volatility rules out its use as a CVD precursor. 

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