Aluminum acetate diethyl-, hydride

The synthesis of the right-wing sector, compound 4, commences with the prochiral diol 26 (see Scheme 4). The latter substance is known and can be conveniently prepared in two steps from diethyl malonate via C-allylation, followed by reduction of the two ethoxy-carbonyl functions. Exposure of 26 to benzaldehyde and a catalytic amount of camphorsulfonic acid (CSA) under dehydrating conditions accomplishes the simultaneous protection of both hydroxyl groups in the form of a benzylidene acetal (see intermediate 32, Scheme 4). Interestingly, when benzylidene acetal 32 is treated with lithium aluminum hydride and aluminum trichloride (1 4) in ether at 25 °C, a Lewis acid induced reduction takes place to give... 

Acetals of aldehydes are usually stable to lithium aluminum hydride but are reduced to ethers with alane prepared in situ from lithium aluminum hydride and aluminum chloride in ether. Butyraldehyde diethyl acetal gave 47% yield of butyl ethyl ether, and benzaldehyde dimethyl acetal and diethyl acetal afforded benzyl methyl ether and benzyl ethyl ether in 88% and 73% yields, respectively [792]. 

Only the trifluoromethyl group has been subjected to reduction in this class of compound. Although not reduced by zinc in acetic acid or by sodium in ethanol, diethyl 2-methyl-4-(tri-fluoromethyl)-1//-pyrrole-3,5-dicarboxylate (1) is reduced at the trifluoromethyl group with an excess of lithium aluminum hydride to give the corresponding tetramethyl derivative 2 sodium borohydridc in ethanol is quite inefficient.104... 

Perhydropyrido[l,2-a]pyrimidine (282) can be converted in an acetic anhydride-formic acid mixture to the 1-formyl derivative, and the 1-formyl group can be reduced to the methyl group with lithium aluminum hydride.342 Treatment with ethylene oxide in the presence of sodium hydroxide leads to the l-(2-hydroxyethyl) derivative,342 and heating with diethylaminoethyl chloride in acetone in the presence of triethylamine gives the l-(2-diethyl-aminoethyl)perhydropyrido [ l,2- ]pyrimidine.27 6,27 7... 

Methoxy-2-phenyl-l-benzotellurinium Perchlorate1 1.81 g (5.0 mmol) of 7-methoxy-2-phenyl-4-oxo-4H-1 -benzotellurin are dissolved in 20 ml] of dry tetrahydrofuran, the solution is cooled to — 78°, and 5.5 ml] of a 20% solution of diisobutyl aluminum hydride in hexane are added dropwise via a syringe. The resultant mixture is then slowly warmed to 20°, 20 m/] of a 1.0 molar sodium hydroxide solution are added, the mixture is stirred at 20° for 1 h, and is then poured into 100 ml] of diethyl ether. The organic phase is washed with brine, dried with anhydrous sodium sulfate, filtered, and concentrated. The residue is dissolved in 25 ml] of acetic acid, 2 ml] of 70% perchloric acid are added, and the solution is allowed to cool. The resultant red precipitate is filtered off, washed with several portions of diethyl ether, and air-dried yield 1.13 g (50%) m.p. 150° (dec). 

Methylphenyl)-telluraxanthene3 1.93 g (4 mmol) of 9-(4-methylphenyl)-telluraxanthylium perchlorate are added to a stirred suspension of 0.5 g (13 mmol) of lithium aluminum hydride and 3.0 g (23 mmol) of aluminum trichloride in 50 ml of absolute diethyl ether at 20°, the mixture is heated under reflux for 1 h, cooled, and 50 ml of ethyl acetate are slowly added. The resultant mixture is poured into 100 ml of 20% aqueous sulfuric acid, the organic layer is separated, the aqueous layer is extracted with two 50 ml portions of diethyl ether, and the combined organic phases are dried with anhydrous sodium sulfate, filtered, and the filtrate is evaporated yield 1.23 g (80%) m.p. 163° (from heptane/benzene). 

Hydroxytelluraxanthene 1.5 g(39 mmol) of lithium aluminum hydride is suspended in 100 ml of absolute diethyl ether, 9.24 g (30 mmol) of thoroughly ground teiluraxanthone are added in small portions to the stirred suspension kept at 20°, and the resultant mixture is stirred for 2 h. 100 ml of ethyl acetate are then added to the cooled, vigorously stirred reaction mixture, followed by a saturated aqueous ammonium chloride solution. The hydrolyzed mixture is filtered, the organic layer is separated, the aqueous phase is extracted twice with diethyl ether, and the organic solutions are combined, washed with water, dried with anhydrous sodium sulfate, filtered, and evaporated. The residue is chromatographed on aluminum oxide with benzene as the mobile phase yield 7.2 g (77%) m.p. 110 112°. 

Silver trifluoroacetate, 327, 328 Silyl ethers, 477-478 Simmons-Smith reagent, 436-437 (3-Sinensal, 283 Sirenin, 424 Sodium, 246, 268, 437 Sodium acetate, 578 Sodium aluminum chloride, 438 Sodium aluminum diethyl dihydride, 438 Sodium aluminum hydride, 316 Sodium amalgam, 41,438-439 Sodium amide, 231, 305,403,439 Sodium amide-Sodium f-butoxide, 439-440 Sodium-Ammonia, 26, 32,134, 260,438 Sodium azide, 9, 77, 210, 323, 440-441 Sodium benzoxide, 111 Sodium bis-(2-methoxyethoxy)aluminum hydride, 164, 293, 360,441-442 Sodium bistrimethylsilylamide, 442-443,... 

Reduction of 2-hydroxycyclobutanone by lithium aluminum hydride gave a 1 1 mixture of cis- and trans-cyclobutane-1,2-diols (80%). Slow distillation of the mixture of these diols in the presence of a catalytic amount of boron trifluoride-diethyl ether complex heated to 230°C in a metal bath gave cyclopropanecarbaldehyde (1) in 65-80% yield, providing an easy route to this aldehyde. Heating the diols in benzene in the presence of p-toluenesulfonic acid was less effective moreover, formation of the cyclopropanecarbaldehyde acetal subsequently occurred under these conditions. ... 

Reducing agents Aluminum hydride. Bis-3-methyl-2-butylborane. n-Butyllithium-Pyridine. Calcium borohydride. Chloroiridic acid. Chromous acetate. Chromous chloride. Chromous sulfate. Copper chromite. Diborane. Diborane-Boron trifluoride. Diborane-Sodium borohydride. Diethyl phosphonate. Diimide. Diisobutylaluminum hydride. Dimethyl sulfide. Hexamethylphosphorous triamide. Iridium tetrachloride. Lead. Lithium alkyla-mines. Lithium aluminum hydride. Lithium aluminum hydride-Aluminum chloride. Lithium-Ammonia. Lithium diisobutylmethylaluminum hydride. Lithium-Diphenyl. Lithium ethylenediamine. Lithium-Hexamethylphosphoric triamide. Lithium hydride. Lithium triethoxyaluminum hydride. Lithium tri-/-butoxyaluminum hydride. Nickel-aluminum alloy. Pyridine-n-Butyllithium. Sodium amalgam. Sodium-Ammonia. Sodium borohydride. Sodium borohydride-BFs, see DDQ. Sodium dihydrobis-(2-methoxyethoxy) aluminate. Sodium hydrosulflte. Sodium telluride. Stannous chloride. Tin-HBr. Tri-n-butyltin hydride. Trimethyl phosphite, see Dinitrogen tetroxide. 

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