Alternate Preparation Procedures

One of the parameters probably most influencing formations of nanocomposites with a high degree of exfoliation is the molecular size of the interlayer anion in the organo-LDH. Costantino et al. [141] have used MDPE without added compatibilizer, mixed with LDH (5%) in a melt-blender mixer and treating at 120°C and 60 rpm. The LDH had been previously intercalated with carboxyadamantane derivative. The presence of 

---

In some microelectronic or higher performance structural applications (e.g., satellites in which reduced levels of UV absorption are desirable, to withstand the harsh space environment), an alternate preparative procedure is employed involving epoxidation via Prileschaiev s reaction, e.g., using peracetic acid. " ... 

In the following, convenient methods for the preparation of the homocyclic sulfur allotropes will be described. Which method to use depends on the amount of material needed, on the skills of the experimentalist and on the chemicals and equipment available. Therefore, several alternative preparation procedures are provided. 

JPC466, 1892B2632). An alternative preparative procedure for benziodoxole 83 involves the oxidation of 2-iodobenzoic acid with acetyl nitrate in acetic anhydride at room temperature followed by aqueous work-up (1992SC1799). 

An alternative preparation of deuterio-Raney nickel is described using a more elaborate purification procedure. There is no evidence however, that the use of this nickel results in a better yield or higher isotopic purity of products from the desulfurization reactions. 

As microwave sample preparation has evolved, standard microwave procedures have been developed and approved by numerous standard methods organisations (ASTM, AOAC International, EPA, etc.), see ref. [64]. Examples are standard test methods for carbon black/ash content (ASTM Method D 1506-97), lead analysis in direct paint samples (ASTM Method E 1645-94), etc. Table 8.15 shows some microwave ashing references (detection weight). A French AFNOR method utilises the atmospheric pressure single-mode microwave method as an alternative sample preparation procedure for Kjeldahl nitrogen determination [84], The performance of a microwave-assisted decomposition for rapid determination of glass fibre content in plastics for QC has been described [85]. 

An alternative preparation of the exocyclic diene (III) was attempted by first thermally decomposing the bromosulfone (I) to yield 2,3-bis(bromomethyl)-1,3-butadiene VI, which, in turn, was allowed to react with aniline following the procedure described by Gaoni (19). 

The 7,8-dihydrodiol of 5-MC (30b) was prepared from 8-hydroxy-5-MC by Method IV (60,103). It was necessary to utilize the 8-rather than the Ot-phenol (i.e. 8-HO-5-MC rather than 7-HO-5-MC), since oxidation of the latter with Fremy s salt was anticipated to take place predominantly in the para position. The 8-hydroxy-5-MC was prepared in our laboratories by a modification of the procedure in Figure 18. An alternative preparation of 8-hydroxy-5-MC via photocyclization of methyl 3-phenyl-2-(l-(6-methoxynaphthyl) propenoate has also recently been described (103). 

For discovery PK assays, the most common sample preparation procedure is protein precipitation161720 24 because it is fast, easy to automate, and requires no method development. While protein precipitation typically will not provide as clean a sample as will alternative procedures, it is sufficient for most discovery PK samples that use HPLC/MS/MS for the analytical step.21101... 

This selectivity can only be achieved with the assistance of functional groups on the alkynes. Thus, if an alternative selective procedure that was independent of the nature of the alkyne substituents were to be available, it would be synthetically very useful. In order to develop such a new procedure for the formation of pyridine derivatives, azazirco-nacyclopentadienes, prepared from an alkyne and a nitrile, are important. As shown in Eq. 2.62, treatment of an azazirconacydopentadiene with an alkyne in the presence of NiCl2(PPh3)2 gives a pyridine derivative as a single product [8b]. Preparative methods for azazirconacydopentadiene derivatives will be discussed below. 

An alternative or additional step to flame annealing is electrochemical or chemical polishing. The fundamental aspects of electropolishing were reviewed recently [185], and a list of polishing procedures and parameters is available [185,186]. This method has been successfully applied to the preparation of gold, silver, and copper electrodes for STM studies [177,180,188]. It is important to note that different mesoscopic structures may arise according to the specific preparation procedures. For example, electropolishing a mechanically prepared Au(lOO) surface followed by... 

By conventional procedures, 106 gm of benzaldehyde reacts in 600 ml of ether with 66 gm of anhydrous hydrazine to give benzalhydrazone which is directly oxidized in anhydrous ether with 300 gm of mercuric oxide to phenyl-diazomethane.) (See Volume I, Chapter 15, p. 398, for oxidation of hydrazones, p. 390 for an alternative preparation of phenyldiazomethane.)... 

The starting molybdenum hydride, Mo(f/5-CsH5)(CO)3H, is prepared according to published procedures.13 As an alternative puriAcation procedure, the molybdenum hydride can be crystallized from cold pentane using the method previously outlined for Fe(C5H5)(CO)2COCH3. The pale pink crystalline solid so obtained can be briefly transferred in air, but prolonged... 

---