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Organic solvents alkyl groups

Reductive alkylation of carbon nanotubes using lithium and alkyl halides yields sidewall-functionalized nanotubes soluble in common organic solvents. Billups group prepared dodecylated SWCNTs from raw HiPCO tubes using lithium and dodecyl iodide in liquid ammonia and demonstrated the occurrence of exten-... [Pg.29]

The species at the centre of tire rings is usually Si or Ge and tire bridging atom is oxygen. In one study tire peripheral hydrogens on tire phtlialocyanine molecules were replaced by alkyl groups and tire resulting polymers could be rendered soluble in ordinary organic solvents [108, 109 and 110]. Successful deposition of several of tliese materials has been achieved and different techniques were employed to study tlieir stmctural properties [109, ill, ill, ill and 1141. [Pg.2620]

Although Pd is cheaper than Rh and Pt, it is still expensive. In Pd(0)- or Pd(ll)-catalyzed reactions, particularly in commercial processes, repeated use of Pd catalysts is required. When the products are low-boiling, they can be separated from the catalyst by distillation. The Wacker process for the production of acetaldehyde is an example. For less volatile products, there are several approaches to the economical uses of Pd catalysts. As one method, an alkyldi-phenylphosphine 9, in which the alkyl group is a polyethylene chain, is prepared as shown. The Pd complex of this phosphine has low solubility in some organic solvents such as toluene at room temperature, and is soluble at higher temperature[28]. Pd(0)-catalyzed reactions such as an allylation reaction of nucleophiles using this complex as a catalyst proceed smoothly at higher temperatures. After the reaction, the Pd complex precipitates and is recovered when the reaction mixture is cooled. [Pg.5]

The replacement of the hydrogen of the methylo1 compound with an alkyl group renders the compound much more soluble in organic solvents and more stable. This reaction is also cataly2ed by acids and usually carried out in the presence of considerable excess alcohol to suppress the competing self-condensation reaction. After neutrali2ation of the acid catalyst, the excess alcohol may be stripped or left as a solvent for the amino resin. [Pg.324]

The triaLkoxy(aryloxy)boranes are typically monomeric, soluble in most organic solvents, and dissolve in water with hydrolysis to form boric acid and the corresponding alcohol and phenol. Although the rate of hydrolysis is usually very fast, it is dependent on the bulk of the alkyl or aryl substituent groups bonded to the boron atom. Secondary and tertiary alkyl esters are generally more stable than the primary alkyl esters. The boron atom in these compounds is in a trigonal coplanar state with bond hybridization. A vacantp orbital exists along the threefold axis perpendicular to the BO plane. [Pg.214]

Organic Halides. Alkyl halides and aiyl halides, activated by election withdrawing groups (such as NO2) in the ortho or para positions, react with alkyleneamines to form mono- or disubstituted derivatives. Product distribution is controlled by reactant ratio, metal complexation or choice of solvent (16,17). Mixing methylene chloride [75-09-2J and EDA reportedly causes a mnaway reaction (18). [Pg.42]

Usually prepared and handled in organic solvent For alkyl groups of <4 carbon atoms, the compounds react vigorously with water and the resulting alkane ignites... [Pg.188]

Dimeric nitroso compounds with tertiary alkyl groups show more tendency toward dissociation into the monomers. For example, 2-methyl-2-nitrosopropane is so volatile in the form of the monomer that it can hardly be isolated from organic solvents. For the prepara-... [Pg.103]

The solubility of phosphoric acid esters in water and organic solvents is controlled by the chain length of the alkyl groups and the ethylene oxide con-... [Pg.590]


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See also in sourсe #XX -- [ Pg.85 ]




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Organic groups

Solvent groups

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