L'acide hydroxylamine-O-sulfonique,réactif de choix pour la conversion d'aldéhydes en nitriles

Hydroxylamine-O-sulfonic acid: a convenient reagent for the conversion of aldehydes into nitriles . Hydroxylamine-O-sulfonic acid (HAS) proved to be an excellent reagent for the conversion of aliphatic, aromatic and heteroatomic aldehydes into nitriles. There, aldehydes in the form of suspension in HAS water solution, react rapidely to give the corresponding nitriles in high yield. Only with formylpyridines could the intermediate oxime-O-sulfonic acids be isolated.     

Formation of Four Different Aromatic Scaffolds from Nitriles through Tandem Divergent Catalysis

A zinc bromide complex, formed by the sequential reaction of nitriles with a Reformatsky reagent and terminal alkynes, is used as an intermediate for divergent palladium‐catalyzed reactions. The reaction pathway of the intermediate is precisely controlled by the choice of the reaction solvent or the palladium catalyst to quickly form four different aromatic scaffolds—arylamines, aminoindenes, pyrroles, and quinolines—starting from readily available nitriles.     

锆氢化反应研究（Ⅳ）：—芳腈的锆氢化反应及其在合成中的应用

芳腈在温和条件下进行锆氢化反应,所得产物经水解得到芳醛;若经酰基化则得到N-酰基不饱和胺。后者不稳定,在室温下与甲醇发生加成反应得N-(α-甲氧基苄基)苯甲酰胺。过量的锆氢化试剂与芳腈反应,继之进行酰基化,得到二元酰基化产物,两个酰基分别加到腈基的碳与氮原子上。     

低价钛引起的芳基二硫醚与α,β-不饱和酯(腈)的反应

芳香族二硫醚在低价钛试剂作用下，S-S键还原断裂成芳硫负离子，再与α,β-不饱和酯(腈)发生Michael加成反应，得到β-硫代酸酯(腈)。     

Preparation of Nitriles by Dehydration of Primary Carboxawides with a Supported phosphorus pentoxide reagent

The use of a supported phosphorus pentoxide reagent in the synthesis of selected nitriles is discussed.     

Diphenylphosphinodithioic acid: A reagent for the conversion of nitriles to thioamides

Diphenylphosphinodithioic acid is a reagent useful for a sequence effecting the hydrolysis of nitriles under mild conditions.     

Bromodimethylsulfonium bromide (BDMS): a useful reagent for conversion of aldoximes and primary amides to nitriles

An operationally simple and high yielding procedure has been developed for the preparation of nitriles from aldoximes and primary amides using bromodimethylsulfonium bromide (BDMS) as a novel and efficient reagent in the absence of any added base or catalyst. The optimal protocol is applicable to access a wide range of cyano compounds including aromatic, heterocyclic, and aliphatic species. The conversion of aldoximes to nitriles takes place at room temperature in acetonitrile, whereas acetonitrile at reflux temperature is required for rapid conversion in the case of primary amides.     

Siliciumorganische verbindungen : LIX. 1,5-Bis(trimethylsilyl)-naphthalin

The addition vs. deprotonation ratio in the reaction of nitriles with n-PrMgBr is increased by complexation of the Grignard reagent with LiClO₄. For nitriles having moderately labile α-hydrogen atoms the deprotonation reaction is almost completely suppressed; but for nitriles having very labile α-hydrogen atoms (CH₃ CN, PhCH₂CN) yields in ketones are increased from 2 to 10–20%.     

One-Pot Three-Component Synthesis of β -Acylaminoketones Containing a Thiophene Ring by the Use of Tetrachlorosilane-Zinc Chloride as a Binary Reagent Under Ambient Conditions

A new route for the synthesis of β -acylaminoketones containing a thiophene ring through multicomponent condensation reaction of different ketones, different aldehydes, and different nitriles with tetrachlorosilane (TCS) and zinc chloride as the binary reagent is described.     

An Efficient Zinc‐Catalyzed Dehydration of Primary Amides to Nitriles

In the present study, the zinc‐catalyzed dehydration of a variety of amides with N‐methyl‐N‐(trimethylsilyl)trifluoroacetamide (MSTFA) as a dehydration reagent into the corresponding nitriles has been examined in detail. With the straightforward and commercially available zinc(II)triflate as the precatalyst and MSTFA, an excellent system has been established to afford nitriles in excellent yields and chemoselectivities. After investigation of reaction conditions and the scope and limitations, several efforts were carried out to understand the reaction mechanism.     

A Simple Method for the Synthesis of Nitriles from Primary Amides Under Neutral Conditions

1-(3-Dimethylaminopropyl)-3-ethylcarbodiimidehydrochloride (EDCI) is a very useful reagent for the preparation of nitriles in good yields under neutral conditions.     

A New Method For The Generation of Nitriles From Aldoximes

A mild and efficient method for the stereoselective dehydration of α-aldoximes to the corresponding nitriles is described which utilises methyl (carboxysulfamoyl)triethylammonium hydroxide inner salt (Burgess reagent) as the dehydrating agent.     

p-TsOH mediated solvent and metal catalyst free synthesis of nitriles from aldehydes via Schmidt reaction

A new and efficient protocol for the conversion of aldehyde into nitriles by modified Schmidt reaction. The reaction is carried out under solvent free condition using sodium azide as a source of nitrogen and catalysed by p-toluene sulphonic acid in presence of silica surface with no side product. This transformation gives good to excellent yield for numerous aromatic, aliphatic and heterocyclic nitriles using very simple reagent. This method has avoided the use of transition metal catalyst, toxic cyanide, hazardous solvent and offers a greener, simple and environment friendly procedure.     

From aldehydes to nitriles, a general and high yielding transformation using HOF·CH3CN complex

N,N-Dimethylhydrazones of aldehydes undergo a rapid oxidative cleavage to form nitriles in very high yields on reaction with HOF·CH₃CN under mild conditions. The reaction is chemoselective and proceeds rapidly without racemization. The nitriles were resistant to further oxidation, even when a large excess of the reagent was employed.     

Rhodium‐Mediated Oxygenation of Nitriles with Dioxygen: Isolation of Rhodium Derivatives of Peroxyimidic Acids

Dioxygen is used as the oxygenation agent in the rhodium‐mediated conversion of nitriles into amides. The characterization of intermediate species and model compounds as well as isotope‐labeling studies provided an insight into the reaction mechanism. The conversions of rhodium hydroperoxido or methylperoxido complexes with nitriles into metallacyclic rhodium‐ κ²‐(N,O)‐peroxyimidate compounds represent essential key steps. The former are accessible from a rhodium(III) peroxido complex and the latter represent rhodium derivatives of Payne’s reagent (peroxyimidic acids).     

α,β-Unsaturated Derivatives of Trivalent Phosphorus in Reactions with Activated Carbonyl Compounds

Abstract

Dialkyl alkynylphosphonites (I) react with esters and nitriles of α-oxocarboxylic acids to give phosphorylated alkanoates, 1,3,2-dioxaphospholanes and l-phosphabicyclohept-4-enes, depending on the nature of the reagent and conditions of the reaction. The reaction of dialkyl alkenylphosphonites (II) with esters and nitriles of α-oxocarboxylic acids predominantly leads to dioxaphospholane derivatives.     

Room temperature dehalogenation of (hetero)aryl halides with magnesium/methanol

Magnesium in methanol was found to be an effective and inexpensive reagent for the dehalogenation of (hetero)aryl chlorides, bromides and iodides under mild conditions. The halogen/hydrogen exchange proceeded at room temperature and tolerated functional groups such as esters, nitriles, alcohols, and alkenes.     

Sulfone–Metal Exchange and Alkylation of Sulfonylnitriles

The first general sulfone–metal exchange is described. Treating substituted 2-pyridylsulfonylacetonitriles with either BuLi or Bu₃MgLi generates metalated nitriles that efficiently intercept a variety of electrophiles to afford quaternary nitriles. The 2-pyridylsulfone is critical for the sulfone–metal exchange because chelation anchors the organometallic proximal to the electrophilic, tetrasubstituted sulfone to override complex-induced deprotonation. Alkylating commercial 2-pyridinesulfonylacetonitrile with mild bases, either K₂CO₃ or DBU, and subsequent sulfone–metal exchange and alkylation rapidly assembles quaternary nitriles by three alkylations, only one of which requires an organometallic reagent.     

Alkylations en α de fonctions organiques par l'intermédiaire de compostés organostanniques

Organotin enolates and α-organotin substituted nitriles or esters which are generally easy to obtain, can be used to alkylate α to functional groups.In the case of organotin enolates, heating with alkylating agents, usually gives monoalkylated products in very good yields: numerous examples with ketones and aldehydes are described.With α-organotin substituted nitriles and esters, direct alkylation does not occur, but good results can be obtained in the presence of either magnesium or lithium bromide, or after a metal exchange reaction with a Grignard or lithium reagent.     

Synthesis of primary arylselenoamides by reaction of aryl nitriles with Woollins' reagent

[Structure: see text] The reaction of aryl nitriles with Woollins' reagent followed by water affords a variety of primary arylselenoamides in 60-100% yield. The first crystal structures of two primary selenoamides are reported.