LAH

A suspension of 7.5 grams LAH in 500ml anhydrous Et20 was magnetically stirred, and heated in an inert atmosphere to a gentle reflux. The condensing Et20 leached out a total of 9.8 g 2-nitro-... 

Reports on EPRI Nickel—Iron Electric Vehicle Project, Argotme National Lahs, Argotme, HI., 1988-1991. 

The least troublesome routes to 3,4-dihydro- and 1,2,3,4-tetrahydro-quinazoline are probably the reduction of quinazoline by sodium borohydride, in water for the former or in methanol for the latter. Both must be isolated as salts. The dihydroquinazoline may be formed also by reduction with LAH in ether (65JHC157). In contrast, 5,6,7,8-tetrahy-droquinazoline is best made by primary synthesis from 2-formylcyclohexanone and for-mamide (57CB942) or from cyclohexanone and trisformamidomethane (60CB1402). 

Hydroxymethylcytosine (967) was isolated only in 1952 from the T-even bacteriophages of Escherichia coli, in which it occurs instead of cytosine in the 2-deoxyribonucleic acid (65MI21304). Of several syntheses described, the most convenient is probably that beginning with ethyl 4-amino-2-methylthiopyrimidine-5-carboxylate which is reduced by LAH to 4-amino-2-methylthiopyrimidin-5-ylmethanol followed by hydrolysis to 5-hydroxymethyl-cytosine (967) (B-68MI21302, B-68MI21306). 

The simplest pyrimidine antibiotic is bacimethrin, 5-hydroxymethyl-2-methoxypyrimidin-4-amine (985), which was isolated in 1961 from Bacillus megatherium and is active against several yeasts and bacteria in vitro as well as against staphylococcal infections in vivo it has some anticarcinoma activity in mice (69MI21301). It may be synthesized by LAH reduction of ethyl 4-amino-2-methoxypyrimidine-5-carboxylate (984) which may be made by primary synthesis in poor yield, or better, from the sulfone (983) (B-68MI21304). 

Properly substituted isoxazolecarboxylic acids can be converted into esters, acid halides, amides and hydrazides, and reduced by lithium aluminum hydride to alcohols. For example, 3-methoxyisoxazole-5-carboxylic acid (212) reacted with thionyl chloride in DMF to give the acid chloride (213) (74ACS(B)636). Ethyl 3-ethyl-5-methylisoxazole-4-carboxylate (214) was reduced with LAH to give 3-ethyl-4-hydroxymethyl-5-methylisoxazole (215) (7308(53)70). 

Oxidation and reduction can initiate changes leading to heterocycle-heterocycle conversions. The reaction of tetraphenylfuran with singlet oxygen (Scheme 34) (B-73MI50303) and that of isoxazoles with LAH (Scheme 35) are examples. 

Despite the strained nature of the azetidin-2-one system, a surprising number of transformations in which the /3-lactam is preserved can be carried out, and some of these will be dealt with in subsequent sections. The highly hindered /3-lactam l-benzyl-3,3,4-triphenyl-azetidin-2-one is claimed to be stable towards hydrochloric acid, sodium and potassium hydroxides, LAH and phenylmagnesium bromide (80IJC(B)702). 

BAMFORD - STEVENS - CAGUOTI- SHAPIRO Olelinalwn Conversion o( ketones to olelins via tosyl hydrazones with NaOR, LAH, LDA or BuLi... 

Cls-1 -dlmethyl-3-phenylazlridlne (2) To a coofed and well stirred suspension of LAH (3 S g, 0 1 mol) m Et20 (100 mL) was added dropwise a solution of 2 2-dichloro-N methyl propiophenone imme 1 (10 8 g, 0 05 mol) m Et20 (100 mL) After overnight reflux the mixture was poured with caution onto ice water aixf the product extracted with Et20 Evaporation ot the solvent gave 8 21 g of 2 (84%), bp 79 82°C... 

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