Sodium isopropoxide

Secondary and tertiary alkyl halides are not suitable because they react with alkox ide bases by E2 elimination rather than by 8 2 substitution Whether the alkoxide base IS primary secondary or tertiary is much less important than the nature of the alkyl halide Thus benzyl isopropyl ether is prepared m high yield from benzyl chloride a pri mary chloride that is incapable of undergoing elimination and sodium isopropoxide... 

Alfin Catalysts. Alfin catalysts (44,45) give polyisoprenes of high /ram-1,4 microstmcture (46). For example, a typical Alfin catalyst gives polyisoprene of 52% /ram-1,4, 27% cis-1,4, 16% 3,4, and 5% 1,2 content (ir analysis) (46). One type of Alfin catalyst consists of aHylsodium, sodium isopropoxide, and sodium chloride (47,48). Because of the mixed microstmcture polyisoprene produced, Alfin catalysts are not used commercially. 

Alkyl or hydride derivatives are formed by addition of a variety of Grignard reagents or sodium isopropoxide to the halide precursors. Cationic complexes may be obtained by the interaction with AgSbFg in the presence of an appropriate... 

Addition of potassium ferf-butoxide or of sodium isopropoxide to the solvent led to ignition of the latter. This was attributed to presence of free metal in the alkoxides, but a more likely explanation seems to be that of direct interaction between the powerful bases and the sulfoxide. 

The catalysts are best prepared in situ by mixing a half-equivalent of the di-chloro-metal aromatic dimer with an equivalent of the ligand in a suitable solvent such as acetonitrile, dichloromethane or isopropanol. A base is used to remove the hydrochloric acid formed (Fig. 35.3). If 1 equiv. of base is used, the inactive pre-catalyst is prepared, and further addition of base activates the catalyst to the 16-electron species. In the IPA system the base is conveniently aqueous sodium hydroxide or sodium isopropoxide in isopropanol, whereas in the TEAF system, triethylamine activates the catalyst. In practice, since the amount of catalyst is tiny, any residual acid in the solvent can neutralize the added base, so a small excess is often used. To prevent the active 16-electron species sitting around, the catalyst is often activated in the presence of the hydrogen donor. The amount of catalyst required for a transformation depends on the desired reaction rate. Typically, it is desirable to achieve complete conversion of the substrate within several hours, and to this extent the catalyst is often used at 0.1 mol.% (with SCR 1000 1). Some substrate-catalyst combinations are less active, requiring more catalyst (e.g., up to 1 mol.% SCR 100 1), in other reactions catalyst TONs of 10000 (SCR 10000 1) have been realized. 

The "Alfin" catalyst (Morton 1964 Reich 1966) is made up to a suspension, in an inert solvent like pentane, of a mixture of an alkylenyl sodium compound (such as allyl sodium), an alkoxide of a secondary alcohol (such as sodium isopropoxide), and an alkali halide (such as sodium chloride). The catalyst is highly specific for the polymerisation of dienes into the 1, 4-forms. 

Potassium methylselenide, 0451 Rhenium hexamethoxide, 2603 Sodium ethoxide, 0878 Sodium isopropoxide, 1270 Sodium methoxide, 0464... 

B. Diazomethane. Sodium isopropoxide method (Note 9). CAUTION... 

Thirty milliliters of a solution of sodium isopropoxide, prepared from 1 g. of sodium and 100 ml. of isopropyl alcohol,... 

Depending on the molar ratio of reactants, the reaction of NaOMe with ZnQ2 in MeOH produces the following complex ions Zn(OMe)2-, Zn(OMe)3MeOH , ZnCl(OMe)J and Zn2Cl4(OMe)2. The last is postulated to have methoxide bridges analogous reactions occur with sodium isopropoxide.687... 

The only other 6-methyl homologue of an active material that was explored chemically, was related to MDA. The ketone (3,4-piperonylacetone, see under MDMA) was methylated with sodium isopropoxide and methyl iodide, and a crystalline oxime was obtained. Reduction with Zn dust gave what appeared to be 2-amino-3-(3,4-methylenedioxyphenyl)butane hydrochloride, but there were sufficient uncertainties (possible dimethylation, only one oxime isolated, the need of strong reducing conditions) that the entire project was placed in, and still is in, an indefinite holding pattern. The similar analogues for DOM are the two Classic Ladies, DAPHNE and ELVIRA, and they, too, are for some time in the future. 

The formation of anthracene 278 (Ar = Ph) directly from the corresponding 2-benzopyrylium salt 30 occurs in low yield, and the final result is dependent both on the nature of the alcohol used and on the concentration of the alkaline solution. Thus, on treatment of this salt 30 with 2% aqueous alkaline solution, 0-naphthol 209 was the only product, whereas with 50% concentration of alkaline solutions, anthracene 278 was formed, but in a yield of less than 20%. A somewhat better yield (40%) of 278 (Ar = Ph) was reached on carrying out the conversion of 2-benzopyrylium salt in isopropyl alcohol containing sodium isopropoxide. However, one can conclude that independent of conditions, the formation of anthracene 278 from 2-benzopyrylium salt in alkaline media does not occur via the intermediate diketone 29 (R1 = Me, R3 = Ph). This is because the latter compound gives rise only to j3-naphthol 209 under the reaction conditions. 

Sodium hypophosphite , see Sodium phosphinate, 4467 Sodium iodate, 4619 Sodium iodide, 4618 Sodium isopropoxide, 1266... 

Sodium isopropoxide Allyl bromide Allyl isopropyl ether Sodium... 

Methyl bromide Sodium isopropoxide Isopropyl methyl ether... 

The reaction of sodium methoxide with isopropyl bromide will proceed mainly by elimination. Methyl bromide is prepared as shown previously sodium isopropoxide can be prepared by adding sodium to isopropyl alcohol. 

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