Reductions with Sulfurated Borohydrides. VI. The Reduction of Nitro, Nitrile, Amide, and Nitroso Groups

Abstract

Aromatic nitro compounds can be reduced with sulfurated sodium borohydride to the corresponding amine in high yields ( Z 80%) without affecting ester, nitrile, ether, halide or olefinic groups also present. With ortho-substituted nitro compounds the yields are around 60%.Primary aliphatic nitro compounds are reduced to the corresponding nitrile in high yields. Secondary aliphatic nitro compounds are reduced to mixtures of ketones and the corresponding oxime. Tertiary aliphatic nitro compounds are not reduced.Aromatic nitriles can be reduced to the corresponding amines with an excess of the reducing agent or converted to the corresponding thioamides with an excess of the nitrile.Amides and nitroso can be reduced to the corresponding amines in moderate yields.Les dkrivks nitrds aromatiques peuvent &tre rdduits en amines avec de bons rendements ( Z 80%) par I'hydrure de bore sulfurk, cette rdduction pouvant etre effectude sans affecter les fonctions ester, nitrile, dther, haloghe ou alckne prdsentes. Avec les dkrivks ortho, les rendements sont de I'ordre de 60%.Les dkrivds nitres aliphatiques primaires sont rkduits en nitriles avec de bons rendements. Les derivks nitrks aliphatiques secondaires sont rdduits en un mklange de cktones et d'oximes correspondantes. Les ddrivks nitrks aliphatiques tertiaires ne donnent pas de rkaction.Les nitriles aromatiques peuvent Ctre rdduits en arnines, avec un excks de rdducteur, ou en thioamides, avec un excks de nitrile.Les amides et les nitroso peuvent Ctre rkduits en amines avec des rendements moddrds.

Reductions with Sulfurated Borohydrides. VII. Reactions with Epoxides

“…This new type of hydride has shown distinctive reducing properties with aldehydes (2), ketones (3), oximes (4), nitro compounds, and nitriles (5). This paper completes this study and describes the reaction of different epoxides with NaBH,S,.…”

Separation of racemic 2,4-dinitrophenyl amino acids on 9-O-(phenyloxycarbonyl)quinine-bonded carbon-clad zirconia in reversed-phase liquid chromatography

“…9-O-(4-Aminophenyloxycarbonyl)quinine was prepared by reducing 9-O-(4-nitrophenyloxycarbonyl)quinine hydrochloride using sulfurated sodium borohydride (NaBH 2 S 3 ) [36] and a modified method of the procedure in the literature [37]. To a suspension of 2.6 g of NaBH 2 S 3 (19.7 mmol) in 100 mL of tetrahydrofuran being refluxed, 10.0 g of 9-O-(4-nitrophenyloxycarbonyl)quinine hydrochloride (19.0 mmol) in 100 mL of THF was added dropwise and allowed to react for 24 h. The reaction mixture was evaporated to dryness and the residual solid was hydrolyzed with 10% hydrochloric acid solution until pH 1 in the presence of 250 mL of diethyl ether.…”

Reactions of NaBH2S3 with some typical organic nitrogen compounds

“…It was found that NaBH2S3 is a mild reducing agent which often shows an intermediate reducing potential between lithium aluminum hydride (LiA1H4) and sodium borohydride (NaBH4), and often gives sulfurated products of great interest. Moreover, the reducing potential of NaBH2S3 was found to be occasionally even more selective than that of LiA1H4 allowing, for example, the reduction of the nitro group in the presence of esters (3).…”

“…In previous papers we have reported the use of sulfurated sodium borohydride (1) for the reduction of some nitrogen compounds (2)(3)(4). It was found that NaBH2S3 is a mild reducing agent which often shows an intermediate reducing potential between lithium aluminum hydride (LiA1H4) and sodium borohydride (NaBH4), and often gives sulfurated products of great interest.…”