Oximes, reduction with lithium aluminum hydride

Phenylacetaldehyde oxime, reduction with lithium aluminum hydride,... 

Oxidative cyclization, substituted stil-benes to phenanthrenes, 46, 91 Oximes, reduction with lithium aluminum hydride, 48, 23 Oximinomalononitrile, from nitrosation of malononitrile, 48,1 reduction with aluminum amalgam, 48,2 ... 

Oximes of a,/i-unsatiirated ketones, on reduction with lithium aluminum hydride, depending on the structure of the ketoxime and on the reaction conditions, yield unsaturated amines, saturated amines, and sometimes aziridines in fair yields [947],... 

Conversion of the keto ketoxime 1 to the exo-exo-amino alcohol 2 has been accomplished by hydrogenation over Adams catalyst and by reduction with lithium aluminum hydride. Amino alcohol 2 has also been prepared from 1 by a two-stage process in which selective reduction of the ketone is carried out with sodium borohydride, and the resultant hydroxy oxime is reduced with lithium aluminum hydride or by hydrogenation over Adams catalyst. ... 

Amide reduction with lithium aluminum hydride, 39, 19 Amine oxide formation, 39, 40 Amine oxide pyrolysis, 39, 41, 42 -Aminoacetanilide, 39, 1 Amino adds, synthesis of, 30, 7 2-Amino-4-anilino-6-(chloro-METHYl) -S-TRIAZINE, 38, 1 -Aminobenzaldehyde, 31, 6 hydrazone, 31, 7 oxime, 31, 7 phenylhydrazone, 31, 7 > -Aminobenzoic add, 36, 95 2-Aminobenzophenone, 32, 8 c-Aminocaproic acid, 32, 13 6-Aminocaproic acid hydrochloride,... 

A transannular route to 1-substituted pyrrolizidines has recently been reported by Wilson and Sawicki. The lactam (79) was prepared by Beckmann rearrangement of the oxime p-toluenesulfonate of cyclohept-4-enone. Reduction with lithium aluminum hydride gave the amine (80), which on treatment with bromine yielded the 1-bromopyrrolizidine (81) in one stereospecific step (95%). The stereochemistry of the product corresponds to a disfavored exo-mode of cyclization by attack of the nitrogen on the bromonium ion. Further modification of this route to produce naturally occurring alkaloids would appear feasible, but has not yet been reported. 

An essentially similar synthesis of 2-amino-2,6-dideoxy-L-talose has been reported by Collins and Overend, involving reduction of the oxime (6) with lithium aluminum hydride. Subsequent acidic hydrolysis of the product yielded a mixture of epimeric glycosides of amino sugars, from which a methyl glycoside of an amino sugar hydrochloride (9), m.p. 265° (dec.), [a]D —8.4° (c, 1.55, in water), was obtained by fractional recrystallization. Acetylation and acidic hydrolysis of this glycoside yielded 2-amino-... 

When dihydroisorubijervine is oxidized with chromic acid in acetic-sulfuric acid there is formed a keto carboxylic acid (XXIII) in which the keto group was demonstrated by the formation of an oxime and a semi-carbazone, and the carboxyl was demonstrated by the formation of a methyl ester (XXIV), whose reduction with lithium aluminum hydride regenerated dihydroisorubijervine (XVIII) (58). 

AletalHydrides. Metal hydrides can sometimes be used to prepare amines by reduction of various functional groups, but they are seldom the preferred method. Most metal hydrides do not reduce nitro compounds at all (64), although aUphatic nitro compounds can be reduced to amines with lithium aluminum hydride. When aromatic amines are reduced with this reagent, a2o compounds are produced. Nitriles, on the other hand, can be reduced to amines with lithium aluminum hydride or sodium borohydride under certain conditions. Other functional groups which can be reduced to amines using metal hydrides include amides, oximes, isocyanates, isothiocyanates, and a2ides (64). 

Intramolecular nitrile oxide—olefin cycloaddition of oxazolidine and thiazoli-dine oximes 407 (R = H, Me R1 =H, Me X = 0, S n = 1,2) proceed stereose-lectively, yielding tricyclic fused pyrrolidines and piperidines. Thus, 407 (n =2 R = H R1 =Me X=S) has been oxidized to the nitrile oxides with sodium hypochlorite, in the presence of triethylamine in methylene chloride, to give the isoxazolothiazolopyridine 408 in 68% yield. Reduction of 408 with lithium aluminum hydride affords mercaptomethylmethylpiperidine 409 in 24% yield (448). 

Derivatives of Aziridines Prepared by Reduction of Oximes with Lithium Aluminum Hydride... 

Reduction of cyclohexanone oxime with lithium aluminum hydride in tetra-hydrofuran gave cyclohexylamine in 71% yield [809], and reduction of ketoximes with sodium in methanol and liquid ammonia [945] or in boiling ethanol [946] afforded alkyl amines, usually in good to high yields. Stannous chloride in hydrochloric acid at 60° reduced the dioxime of 9,10-phenanthra-... 

The Schmidt reaction affords both possible isomers when applied at the sulfide oxidation level, and also with the sulfoxide, no trace of sulfoximine being found (75CJC276). Reduction of the oxime to the amine with lithium aluminum hydride is significantly improved by the presence of titanium tetrachloride (78KGS1694). 

The second synthesis of lasubine II (6) by Narasaka et al. utilizes stereoselective reduction of a /3-hydroxy ketone O-benzyl oxime with lithium aluminum hydride, yielding the corresponding syn-/3-amino alcohol (Scheme 5) 17, 18). The 1,3-dithiane derivative 45 of 3,4-dimethoxybenzaldehyde was converted to 46 in 64% yield via alkylation with 2-bromo-l,l-dimethoxyethane followed by acid hydrolysis. Treatment of the aldol, obtained from condensation of 46 with the kinetic lithium enolate of 5-hexen-2-one, with O-benzylhydroxylamine hy-... 

The oximes of the 1-butyl and 1-phenyl aldehydes (148) were reduced with zinc and hydrochloric acid to give 1-butyl- and l-phenyl-3-aminomethyl-4-methyl-7-azaindole, in 63 and 65% yield, respectively. Reduction of the 1-phenyl oxime with lithium aluminum hydride, however, was accompanied by reduction of the pyrrole ring to give the corresponding 3-aminomethyl azaindoline in 80% yield. 9... 

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