Aluminium chloride reagent

The benzylidene derivative (94) has been converted into the alcohol (95) [97, 98] using the diborane — trimethylamine — aluminium chloride reagent [99] and into the diol (96) [95, 100, 101]. Veyrieres has converted methyl P-lactoside (and the corresponding allyl lactoside) into the 3-O-allyl ether (97) in good yield [102] by alkylation of the dibutylstannylene derivative in the presence of tetrabutylammonium iodide [103, 104], and this was converted into the alcohol (98) and the triol (99) [105]. Veyrieres [106] has also converted (97) into the per-p-bromobenzyl derivative and deallyl-ated the product to give a derivative with a free 3 -hydroxyl group. The diol (100) [107] has been converted by the stannylation procedure [108, 109] into the alcohol (101) [110, 111]. The partially acetylated benzyl P-lactoside (103) [101,112, 113] has been converted into the alcohol (104) via the orthoacetate [113]. 

Aluminiwn Chloride Reagent Reaction Procedure Tested Aluminium Chloride Reagent 149... 

Mixed lithium aluminium hydride-aluminium chloride reagents... 

The yield of iso-propylbenzene is influenced considerably by the quality of the anhydrous aluminium chloride employed. It Is recommended that a good grade of technical material be purchase in small bottles containing not more than 100 g. each undue exposure to the atmosphere, which results in some hydrolysis, is thus avoided. Sealed bottles containing the reagent sometimes have a high internal pressure they should be wrapped in a dry cloth and opened with care. 

Lithium aluminium hydride LiAlH is a useful and conveuient reagent for the selective reduction of the carbonyl group and of various other polar functional groups. It is obtained by treatment of finely powdered lithium hydride with an ethereal solution of anhydrous aluminium chloride ... 

The first examples of alkylation reactions in molten salts were reported in the 1950 s. Baddeley and Williamson performed a number of intramolecular cycliza-tion reactions [76] (Scheme 5.1-46), carried out in mixtures of sodium chloride and aluminium chloride. The reactions were run at below the melting point of the pure salt, and it is presumed that the mixture of reagents acts to lower the melting point. 

A good grade of technical anhydrous aluminium chloride was used to obtain the results given in the procedure. The yield falls off considerably when the quality of this reagent is not good. 

Brown and Young410,411 studied the benzoylation of benzene and toluene by benzoyl chloride catalysed by aluminium chloride at 25 °C in nitrobenzene as solvent. For a given concentration of reagents, the rate equation was... 

Using 1,2-dichloroethane as solvent, Brown et al. 16 have also studied the acetylation reaction, with acetyl chloride and aluminium chloride as reagents at 25 °C. The appropriate data for benzene are given in Table 111 and by comparison with Table 109 it appears that acetylation occurs some 300 times as fast as benzoylation. 

Aluminium chloride has to be introduced gradually in the naphthalene/benzoyl chloride mixture and the mixture of these two reagents has to be brought to a temperature that is high enough so that it is in the molten state. Crystallised naphthalene residues are enough to cause the medium to detonate. 

A variety of products have been isolated in earlier studies of the phosphorus trichloride-tris(dimethylamino)phosphine-aluminium chloride system, and a reinvestigation has now shown that the nature of these products is dependent on the sequence in which the reagents are allowed to react with each other. The most interesting new compounds obtained from this system in dichloro-... 

In the preparation of a series of substituted phenylethylenediamines, it is essential to add the reagents to an aromatic solvent at 30-80°C in the order aniline, then aluminium chloride, then ethylenimine to prevent uncontrollable exothermic reaction. 

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