Materials for the Preparation

Generally, organic and inorganic water-soluble materials are used. These materials are not pure and contain about 2-5 % of impurities some are harmfirl and others generally inert, but which are difficult to remove. They are divided into cations and anions. 

The sirlfates are problematic as they are not easy to be removed during calcina-ti(Mi. On the other hand, nitrates are more soluble, volatile, and easily removed during the thermal treatment, but can interact with the support and retained as nitrate or nitrite residues. 

In turn, carbonates, which are relatively soluble, can easily decompose in CO2 during the heat treatment or calcination, but can also be retained as residue of coke and carbon, which depends on interaction with the used support. This coke can only be eliminated under specific conditions. 

Finally, the chlorides have strong bonds with the support, and so retain chlorine that is difficult to be removed at low temperatures. 

The ammonium ions are soluble and are readily decomposed into NH3, forming complexes. The sodium or potassium ions are retained in the support and are not easily removed. 

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These products are used as starting material for the preparation of 2-substituted thiazol-4-ylacetic acids. a-Benzoyloxythiopropionamide and a-benzoyloxy-a-benzoylthioacetamide condensed with an equimolar amount of an a-haloketone in alcoholic solution yield the following compounds (409, 419, 569) 24, Rj = CH3, PhCO, R2 = Me... 

The major uses of ethylene and propene are as starting materials for the preparation of polyethyl ene and polypropylene plastics fibers and films These and other applications will be described in Chapter 6... 

ETHYLENE We discussed ethylene production in an earlier boxed essay (Section 5 1) where it was pointed out that the output of the U S petrochemi cal industry exceeds 5 x 10 ° Ib/year Approximately 90% of this material is used for the preparation of four compounds (polyethylene ethylene oxide vinyl chloride and styrene) with polymerization to poly ethylene accounting for half the total Both vinyl chloride and styrene are polymerized to give poly(vinyl chloride) and polystyrene respectively (see Table 6 5) Ethylene oxide is a starting material for the preparation of ethylene glycol for use as an an tifreeze in automobile radiators and in the produc tion of polyester fibers (see the boxed essay Condensation Polymers Polyamides and Polyesters in Chapter 20)... 

Give the structures of three isomeric dibromides that could be used as starting materials for the preparation of 3 3 dimethyl 1 butyne J... 

Alcohols are versatile starting materials for the preparation of a variety of organic func tional groups Several reactions of alcohols have already been seen m earlier chapters and are summarized m Table 15 2 The remaining sections of this chapter add to the list... 

The linear a olefins described m Section 14 15 are starting materials for the preparation of a variety of aldehydes by reaction with carbon monoxide The process is called hydroformylation... 

The carboxylic acid produced m the greatest amounts is 1 4 benzenedicarboxylic acid (terephthahc acid) About 5 X 10 Ib/year is produced m the United States as a starting material for the preparation of polyester fibers One important process converts p xylene to terephthahc acid by oxidation with nitric acid... 

Section 20 20 Nitriles are useful starting materials for the preparation of ketones by reaction with Grignard reagents... 

The value of alkyl halides as starting materials for the preparation of a variety of organic functional groups has been stressed many times In our earlier discussions we noted that aryl halides are normally much less reactive than alkyl halides m reactions that involve carbon-halogen bond cleavage In the present chapter you will see that aryl halides can exhibit their own patterns of chemical reactivity and that these reac tions are novel useful and mechanistically interesting... 

Hecogenin has been used as starting material for the preparation of betamethasone (78) this genin is found in the sisal plant, sisalana. The... 

Pubhcations have described the use of HFPO to prepare acyl fluorides (53), fluoroketones (54), fluorinated heterocycles (55), as well as serving as a source of difluorocarbene for the synthesis of numerous cycHc and acycHc compounds (56). The isomerization of HFPO to hexafluoroacetone by hydrogen fluoride has been used as part of a one-pot synthesis of bisphenol AF (57). HFPO has been used as the starting material for the preparation of optically active perfluorinated acids (58). The nmr spectmm of HFPO is given in Reference 59. The molecular stmcture of HFPO has been deterrnined by gas-phase electron diffraction (13). 

Hafnium Carbonate. Basic hafnium carbonate [124563-80-0], Hf2(0H)4C02 XH20, is prepared as a wet paste by reaction of a slurry of basic hafnium sulfate [139290-14-5], Hf 02(S0 2 XH20, and sodium carbonate, then filtering. The basic carbonate has a short shelf life and is preferably prepared as needed. It is a starting material for the preparation of various hafnium carboxylates. 

Iron(III) acetate [1834-30-6], Ee(C2H202)3, is prepared industrially by treatment of scrap iron with acetic acid followed by air oxidation. Iron(III) acetate is used as a catalyst in organic oxidation reactions, as a mordant, and as a starting material for the preparation of other iron-containing compounds. 

Bacterial removal of sterol side chains is carried out by a stepwise P-oxidation, whereas the degradation of the perhydrocyclopentanophenanthrene nucleus is prevented by metaboHc inhibitors (54), chemical modification of the nucleus (55), or the use of bacterial mutants (11,56). P-Sitosterol [83-46-5] (10), a plant sterol, has been used as a raw material for the preparation of 4-androstene-3,17-dione [63-05-8] (13) and related compounds using selected mutants of the P-sitosterol-degrading bacteria (57) (Fig. 2). 

The dinuclear ion Mo2(S2) g (F - prepared from the reaction of molybdate and polysulfide solution (13) is a usehil starting material for the preparation of dinuclear sulfur complexes. These disulfide ligands are reactive toward replacement or reduction to give complexes containing the Mo2S " 4 core (Fig. 3f). 

Gibbsite is aii important technical product and world production, predominantly by the Bayer process, is more than 50 million metric tons aimuaHy. Alost (90%) is calcined to alumina [1344-28-1 j, Al202, to be used for aluminum production. Tlie remainder is used by the chemical industry as filler for paper, plastics, rubber, and as the starting material for the preparation of various aluminum compounds, alumina ceramics, refractories, polishing products, catalysts, and catalyst supports. 

The major source of raw materials for the preparation of fatty amines is fats and oils such as tallow, and coconut, soya, and palm oils. Ethyl Corporation uses petrochemicals as raw materials to prepare alkyl dimethyl and dialkylmethyl tertiary fatty amines, trademarked as AE)MA and DAMA products, which can be suppHed as single-carbon chain-length cuts or custom blends (13). Commercially available high purity fatty amines are Hsted in Table 3. Cost of the amines can vary owing to supply of raw materials. 

Cobalt(II) hydroxide [1307-86-4], Co(OH)2, is a pink, rhombic crystalline material containing about 61% cobalt. It is insoluble in water, but dissolves in acids and ammonium salt solutions. The material is prepared by mixing a cobalt salt solution and a sodium hydroxide solution. Because of the tendency of the cobalt(II) to oxidize, antioxidants (qv) are generally added. Dehydration occurs above 150°C. The hydroxide is a common starting material for the preparation of cobalt compounds. It is also used in paints and Hthographic printing inks and as a catalyst (see Paint). 

Acyloins are useful starting materials for the preparation of a wide variety of heterocycles (e.g., oxazoles and imidazoles ) and carbocyclic compounds (e.g., phenols ). Acyloins lead to 1,2-diols by reduction, and to 1,2-diketones by mild oxidation. 

Some aulfinates are commercially available. They may be used as starting materials for the preparation of aulfonyl cyanides also. Yields, however, are not significantly better than when the much cheaper and more readily available sulfonyl chlorides are used as starting materials. Good to excellent results are obtained, even when starting from rather impure sulfonyl chlorides. Illustrative examples are given in Table I. 

Thehaine stands at the other end of the series from morphine and is a convulsant poison rather than a narcotic (see table, p. 261). Hildebrandt states that it excites the reflexes of cold-blooded animals but in dogs it exerts a narcotic and anti-emetic effect resembling that of morphine rather than that of chloromorphide. The alkaloid is scarcely used in medicine as such, but is a primary material for the preparation of certain of the modern morphine derivatives, such as hydroxydihj dro-codeinone and methyldihydromorphinor.e. 

Hydroquinine (Dihydroquinine), C20H26O2N2.2H2O. This base was isolated by Hesse from the mother liquors of quinine sulphate manufacture and is present to the extent of 5 to 6 per cent, in commercial sulphate of quinine, from which it is best isolated by the mercuric acetate process. The demand for hydroquinine as such and as a material for the preparation of hydrocupreine has led to its manufacture from quinine by catalytic hydrogenation. It crystallises from ether or benzene in needles, m.p. 173 5° (dry), — 235 7° (c = M/40, N/10 H2SO4) or... 

Salicylic acid, the starting material for the preparation of aspirin. 

One of the chief uses of chloromethane is as a starting material from which silicone polymers are made. Dichloromethane is widely used as a paint stripper. Trichloromethane was once used as an inhalation anesthetic, but its toxicity caused it to be replaced by safer materials many years ago. Tetrachloromethane is the starting material for the preparation of several chlorofluorocarbons (CFCs), at one time widely used as refrigerant gases. Most of the world s industrialized nations have agreed to phase out all uses of CFCs because these compounds have been implicated in atmospheric processes that degrade the Earth s ozone layer. 

Because vicinal dihalides are prepared by addition of chlorine or bromine to alkenes (Section 6.14), alkenes, especially teiminal alkenes, can serve as starting materials for the preparation of alkynes as shown in the following example ... 

Ethyl acetoacetate (acetoacetic ester), available by the Claisen condensation of ethyl acetate, has properties that make it a useful starting material for the preparation of ketones. These properties are... 

It IS the stantng material for the preparation of nearly all manganese chemicals and is used m tenilizers tn arca.s of the world where there is a deficiency of Mn in the soil, since Mn is an essential irace element in plani growth. The anhydrous salt has a surprising Ihermal siabiliiy it remains unchanged even at red heal, whereas the solfates of Fe , Co" and Ni" all decompose under these conditions. 

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