Aluminium recrystallization

Acrylic acid (AA) and methacrylic acid (MAA) (purchased from Merck) are freed from inhibitor on a neutral aluminium oxid column and distilled. Acrylamide (AM) from Kebo, Stockholm, is recrystallized once from chloroform solution before use. Other monomers of analytical grade were purchased from Merck and used as received crotonic acid (CA), tiglic acid (TA), 3-methyl crotonic acid (3-MCA), and a-methyl cinnamic acid (oi-MCia) (Table 1). Benzophenone (analytical grade, Kebo) and acetone (spectroscope grade, Merck) were used as supplied. 

Durene is quite volatile, and should not be allowed to remain exposed to the air any longer than necessary. It is also quite volatile with alcohol, and the mother liquors resulting from the recrystallizations should be distilled the alcoholic distillate is used for further recrystallizations, and the residues may be worked up for durene by heating with aluminium chloride. 

General procedure for the cyclization of f-(aryltelluro)propenoyl chlorides with aluminium chloride The propenoyl chloride derivatives were dissolved in methylene chloride (1 g, 10 mL) under a nitrogen atmosphere. The solution was cooled to -78°C, and 1.1 equiv of aluminium chloride was added. The cooling bath was removed and the reaction was allowed to warm to room temperature. After stirring for 1 h at room temperature, the reaction mixture was poured into ice-water, and the products were extracted with several portions of methylene chloride. The combined methylene chloride extracts were dried over sodium sulphate and concentrated. The residues were recrystallized from methanol if NMR spectroscopy showed a single product. 

Hydroxy-5,6,7,8-tetrahydro-l-aeetonaphikone—By use of a procedure similar to that of O Farrell et al. [3], 1-75 g (0-00858 mole) of methoxyketone and 13 g of aluminium chloride were heated for 4 hours in 40 ml of benzene, the temperature being raised gradually from 45° to reflux. The dark mixture was treated with ice and hydrochloric acid. The benzene layer was separated and the aqueous layer extracted twice with ether. The combined extracts were shaken twice with 2% sodium hydroxide. Acidification yielded 0-92 g (56%)t of crude hydroxyketone, m.p. 110-115° (drops at 95°). Two recrystallizations from petroleum ether (b.p. 30-65°) afforded transparent rods which melted sharply at 111-112° and quickly resolidified to prisms, m.p. 1)5-116° lit. m.p. 112-113° [3]. 

To 10.65 parts acetic anhydride there were added, with cooling, 8 parts l-(3-trifluoromethylphenyl)-2-aminopropane and 100 parts water. The mixture was neutralized with 30 parts sodium carbonate. The organic layer was extracted twice with 50 parts ether. The ether solutions were washed with 25 parts water and dried over potassium carbonate. On distillation there were obtained 9 parts l-(3-trifluoromethylphenyl)-2-acetyl-aminopropane. 9 parts of it were reduced in solution in 100 parts ether with 1.7 parts lithium and aluminium hydride with 20 parts ether. The suspension was refluxed for 4 hours, hydrolysed with 2 parts water, 2 parts 4 N sodium hydroxide and then 6 parts water. The precipitate was drained washed with 50 parts ether, the filtrate was extracted twice with 50 parts 0.5 N sulfuric acid. The acidic layers were separated by sedimentation and neutralized with 100 parts 4 N sodium hydroxide, the separated amine was extracted with 200 parts ether. There were obtained 6 parts l-(3-trifluoromethylphenyl)-2-ethylaminopropane (boiling point 108°-112°C at 12 mm). The hydrochloride thereof was recrystallized from mixture of ethyl alcohol and ether (melting point 166°C). 

The donor-acceptor complex (2) is isolated from tetrachloromethane solution ( ]. = 2.2), the ionic salt (3) from chloroform solution (er = 4.9). When dissolved in chloroform, the donor-acceptor complex recrystallizes as the ionic salt. Similarly, the ionic salt is converted to the donor-acceptor complex when dissolved in tetrachloromethane. This result shows that in solution an equilibrium exists between the two forms. The isolation depends on the solvent used for recrystallization. Similar results have been obtained in the case of the adduct between acetyl chloride and aluminium trichloride, which is un-ionized in chloroform, but completely ionized in nitrobenzene [160],... 

Methyl acrylamidoglycolate methylether (MAGME) (American Cyan-amid) was filtered while warm and recrystallized from xylene (mp 70 73 C). All other monomers were freed from inhibitor on an aluminium oxide column. p-Trimethylsilylstyrene was synthesized from p-chlorostyrene using a Grignard reaction and chlorotrimethylsilane. Azobisisobutyronitrile (AIBN) was used as free-radical initiator in all polymerizations and carbon tetrabromide as chain-transfer agent. Polymerizations were carried out at 60 C in a 50 50 mixture of toluene and butanol under a nitrogen atmosphere. The reaction was carried out for 3,5 h and the formed polymer precipitated in cold diethylether. It was then redissolved and repreciptated prior to further use. once more IR spectra were recorded on a Perkin Elmer 1710 FTIR and NMR on a 200 MHz Bruker WP 200. FTIR was used to determine the co-polymer composition. 

Potassium diphenylarsenide-2-dioxane reacts with (—)-menthyl chloride in boiling tetrahydrofuran to give (lS,2S,5i )-( + )-neomenthyldiphenylarsine, (S)-( + )-175 (neo-menars). The arsine was obtained as colourless needles in ca 40% yield after recrystallization from warm methanol (Table 9). The neomenthylarsine, upon reaction with benzyl bromide in benzene, affords the epimeric (li ,2S,5i )-benzylmenthylarsonium bromide, (i H-f-)-176, which, upon reduction with lithium aluminium hydride, affords (l/t,2S,5K)-diphenylmenthylarsine, (J )-( — )-177 (menars) (equation 25). 

Surprisingly simple Friedel-Crafts reactions introduce ferrocene units into amphiphiles. For example, 11-bromo-undecanoyl chloride can be added directly to ferrocene in dichloromethane with aluminium chloride as a catalyst. The corresponding (11-bromo-undecanoyl) ferrocene can be isolated via simple recrystallization, and the ketone removed by amalgamated zinc (does not remove the bromide). The bromide can finally be substituted by alcohols and amines to yield ethers and ammonium salts (Scheme 2.13). 

It can be seen from Fig. 12.20 that berlinite amorphizes at a pressure of 33 GPa and amorphous aluminium phosphate recrystallizes at a pressure of 27 GPa. The observed phase transitions are in accord with the experimental results (Kruger and Jeanloz, 1990), but the transition pressures are different from experiment (15 + 3 GPa and 5 GPa, respectively, with a hysteresis of about 13-15 GPa). In this study the hysteresis is about 6 GPa. This discrepancy could be attributed to several factors. First, the fact that a perfect crystal is... 

The Al-O-Al BAD is depicted in Fig. 12.24. This graph shows the two transitions clearly, since the shape of the BAD changes drastically during both amorphization and recrystallization processes. A flat curve is observed at pressures below 24 GPa because at these pressures there is only one aluminium atom around each oxygen atom, with this BAD having two main peaks at 120° and 139°. 

As noted above, upon depressurization the amorphous A1P04 recrystallizes. This is the point at which the percentage of four-coordinated aluminiums jumps from 2% to 59%, while the percentage of five-coordinated aluminiums decreases from 48% to 38% and that of the six-coordinated aluminium atoms decreases sharply from 38% to just 3%. The seven-coordinated species disappear altogether upon recrystallization. As the crystal is depressurized... 

Six crystalline phases of non-solvated AlHg can be produced by the desolvation of aluminium hydride etherate in the presence of small quantities of LiAlH4. The most stable form, a-AlHg, is produced from the solid metastable phases, or by recrystallization from a refluxing mixture of and Et20. ... 

Diastereoselective complexation of a chiral [antagonist] ketone with a racemic aluminium Lewis acid catalyst effectively removes one enantiomer of the latter, leaving the uncomplexed antipode free to function as a chiral Lewis acid. E Asym. heterodiene synthesis. 0.1 eq. D-3-bromocamphor, 1.05 eqs. startg. siloxydiene, and benzaldehyde added sequentially to 0.1 eq. of the racemic aluminium complex in degassed methylene chloride at —78°, stirred for 3 h, then subjected to acidic work-up (2S,3S)-product. Y 78% (e.e. 82%, upgraded to > 98% by one recrystallization with ca. 60% recovery). F.e.s. K. Maruoka, H. Yamamoto, J. Am. Chem. Soc. Ill, 789-90 (1989). 

Aluminium and its alloys are used extensively in research reactors as core components such as fuel element claddings, channel tubes and pipes, and this is mainly because of aluminium s low thermal neutron absorption cross-section and low density, and the absence of any structural transformation up to its melting point. In addition, upon irradiation it does not produce any long lived radionuclides except for Al, which has a half-life of only 2.24 minutes. Radiation damage in aluminium and its alloys is insignificant because of their low recrystallization temperatures. 

Figures 3.1-57a and 3.1-57b show typical softening curves for aluminium alloys in three characteristic stages recovery, recrystallization, and grain-growth. In the case of the untreated continuously cast and rolled strip shown in Fig. 3.1-57a, recrystallization will occur at temperatures between about 260 and 290 °C. In Fig. 3.1-57b, recrystallization starts after about half an hour and is complete after about an hour. The...

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