Long-chain aliphatics

The relationship between structure and properties of polyethylene is largely in accord with the principles enunciated in Chapters 4, 5 and 6. The polymer is essentially a long chain aliphatic hydrocarbon of the type... 

By application of the Schmidt reaction, the conversion of a carboxylic acid into an amine that has one carbon atom less than the carboxylic acid, can be achieved in one step. This may be of advantage when compared to the Curtius reaction or the Hofmann rearrangement, however the reaction conditions are more drastic. With long-chain, aliphatic carboxylic acids yields are generally good, while with aryl derivatives yields are often low. 

The phenylacetaldehyde reductase involved in the degradation of styrene is also able to accept long-chain aliphatic aldehydes and ketones, and halogenated acetophenones (Itoh et al. 1997). 

Related to these cements are the long chain aliphatic acids and aryl-substituted butyric acid (Skinner, Molnar Suarez, 1964). These materials are on the market as non-eugenol cementing agents but they are unduly... 

Polyalphaolefin Hydraulic Fluids. No studies were located regarding absorption in humans or animals after inhalation exposure to polyalphaolefin hydraulic fluids or their major components. Based on physicochemical similarities with mineral oils (i.e., long-chain aliphatic hydrocarbons are predominant... 

Unlike the crystalline cycloamylose complexes, combining ratios of host to guest in solution are usually 1 1. A notable exception is the interaction of the cycloamyloses with long chain aliphatic carboxylic acids. Solubility plots suggest that as many as four cycloheptaamylose molecules may interact with a single molecule of dodecanoic acid (Schlenk and Sand, 1961). In analogy to the crystalline state, cycloamyloses may form channels in solution in order to accomodate extended chains. 

Raghavan and coworkers have reported on the preparation of 4-hydroxybenzoic add esters (parabans) possessing antimicrobial activity by esterification of 4-hydroxybenzoic acid (Scheme 6.153) [299]. Optimum results were obtained using the alcohol (1-butanol) as solvent in the presence of catalytic amounts of zinc(II) chloride or p-toluenesulfonic acid (pTsOH) under atmospheric conditions. After 5 min of microwave irradiation at 120 °C, ca. 40% conversion to the ester was observed. Related studies on the synthesis of long-chain aliphatic esters have been described by Mariani and coworkers [300]. 

Immobilized cryptates. Like the crowns, cryptates have been immobilized on polymeric backbones. A typical system is given by (221) (Cinquini, Colonna, Molinari, Montanari Tundo, 1976). In this case, the polymeric matrix is polystyrene cross-linked with p-divinyl benzene and the cage is connected to this matrix via a long-chain aliphatic spacer group. This reagent is quite effective as a (triphase) transfer catalyst. 

Ligand-free catalysts have been prepared from the following types of nickel(II) compounds nickel salts of long-chain aliphatic or aromatic carboxylic acids (10, 11) or of sulfonic acids (11), nickel enolates of /3-diketones (11) [e.g., nickel acetylacetonate (4, 12)] or their imino derivatives (11, 13), nickel phenolates (11), dithiocarbamates (14), and mer-captides (15). 

Fractionation of mycobacteria resulted in the identification of two cellular immunostimulatory components, namely TDM and MDPs. Both are normally found in association with the mycobacterial cell wall. TDM is composed of a molecule of trehalose (a disaccharide consisting of two molecules of a-D-glucose linked via an a 1-1 glycosidic bond), linked to two molecules of my-colic acid (a long-chain aliphatic hydrocarbon-based acid) found almost exclusively in association with mycobacteria. TDM, although retaining its adjuvanticity, is relatively non-toxic. 

Tewari, R.S. and Shukla, R., Organophosphorus compounds. Addition reaction of 0,0-dialkyl hydrogen phosphites with substituted aromatic and long chain aliphatic aldehydes, Labdev, Part A, 9,112,1971. 

See also van der Waals forces Long-chain aliphatic acids, 20 97 Long chain amphiphiles, 24 123 Long-chain branching, 19 840 extent of, 19 839 in HDPE, 20 160-162 in LDPE, 20 220, 232-234 in LDPE resins, 20 215 quantifying, 20 228-229 Long-chain polyphosphates,... 

Additives may exert not only a physical but also a chemical influence on the coupling suspension long-chain aliphatic or cycloaliphatic amines RNH2, which react partially with the pigment molecules, will enhace the effect of other additives. The carbonyl function of the acetyl group is converted to a ketimine (azomethine) or, in the presence of the enol form, it reacts to form an alkylammonium enolate [5],... 

Luciferase from bacterial sources catalyses the oxidation of long chain aliphatic aldehydes and requires the coenzyme FMN. The wavelength of the emitted radiation in this reaction is approximately 490 nm ... 

Fatty acids are long chain aliphatic monocarboxylic acids. 

The introduction of any flexible molecular repeat units, such as long-chain aliphatic diols or diacids, large hydrocarbon phases, such as C36 dimer acid,... 

Gross, J.H. Veith, H.J. Unimolecular Fragmentations of Long-Chain Aliphatic Iminium Ions. Org. Mass Spectrom. 1993, 28, 867-872. 

Many workers have shown [3,19] that the gallery height in LDHs containing long chain aliphatic carboxylate, dicarboxylate, sulfonate or sulfate guests increases as the chain length increases. For the case of o, 6t)-dicarboxylate anions OOC(CH2)nCOO , the basal spacing shows a mean increase of 0.127 nm/CH2 from n = 3 to 12 as shown in Fig. 21 [213] for Mg/Al LDH... 

This arrangement is also similar to that adopted by the headgroups of long chain aliphatic acids in LB films. Intercalation at over 100% AFC was shown to be a result of co-intercalation of sodium cations or neutral stearic acid molecules. In the case of tra 5-CH3(CH2)7CH = CH(CH2)7COOH (elaidic acid), two different intercalated LDHs with a monolayer of elaidate anions... 

S, 5i )-2-methylhexanolide and (i )-hexadecanolide were synthesized as examples of a new protocol for asymmetric reduction of long chain aliphatic ketones. 

---