Alcohol To nitrile

Primary (1°) alkyl chloride to ethyl ester 2.10 alcohol to nitrile... 

The base-catalyzed addition of alcohols to nitriles to give imidates proceeds well, if there are electron-attracting groups in the a-position. In such cases the Pinner synthesis is less effective, because nitrile basicity is less. TTiis shows that both methods are complementary. Recently attention has been paid to the long-known addition of alcohols to trichloroacetonitrile, since it was found that imidates prepared from protected saccharides, amino alcohols etc. and trichloroacetonitrile are useful reagents for the synthesis of nucleosides, disaccharides and other natural products. The trichloroacetimidic acid esters (240 equation 131) of fluorinated, unsaturated aliphatic alcohols °° and benzyl alcohol have been prepared for synthetic purposes. 

Ritter reaction. Formation of amides by addition of olefins or secondary and tertiary alcohols to nitriles in strongly acidic media. 

Nitriles. A modified Mitsunobu reaction that transforms alcohols to nitriles employs BujP and AfA .A A -tetramethylazodicarboxamide as activator and acetone cyanohydrin as pronucleophile. 

A collection of results obtained with the most effective catalyst systems is summarized in Figure 6.4. Noteworthy examples include the oxidation of a-aminoalcohols with no loss in enantiopurity and the oxidation of cis-allyhc alcohols without Z E isomerization. Stahl also demonstrated the chemoselective oxidation of primary diols to form lactones [22]. While ABNO provides efficient oxidation of symmetric diols, TEMPO discriminates between subtle steric differences in nonsymmetrical substituted diols. Cu/nitroxyl catalysts have also been applied to a variety of tandem reactions [23], perhaps the most noteworthy of which is the conversion of primary alcohols to nitriles via in situ condensation of ammonia with the aldehyde and subsequent dehydrogenation of the primary imine to the nitrile (Figure 6.5) [24]. 

Figure 6.5 Aerobic oxidation of primary alcohols to nitriles by Huang and coworkers [24b].

The tandem oxidation processes employing Mn02 continue to be applied to functional group interconversions. A new entry in this area is the direct conversion of activated alcohols to nitriles via an intermediate aldehyde followed by its corresponding imine (eq 104). 52... 

A rapid conversion of alcohols to nitriles through chlorides prepared in situ has been published. Good yields of a-acoxy-nitriles can be obtained from cyanohydrins and a,/ -unsatd. aldehydes carrying electron-attracting substituents . 

The absolute reaction rate of methyl acrylate and the nitrile ylide derived from 2,3-diphenyl-2/f-azirine at 25°C has been estimated as 7.6 X 10 AT sec. Inductive effects exerted by substituents on the nitrile ylide also have an important effect on the regioselectivity of the cycloaddition. Benzonitrilio-hexafluoro-2-propanide (44) and methyl acrylate yield products with inverse regioselectivity as compared with the reactions of the related benzonitrilo-2-propanide 47. The difference in regioselectivity has been attributed to the larger coefficient at the trisubstituted carbon atom of the gem-trifluoromethyl substituted nitrile ylide 44. This result parallels the different mode of addition of alcohols to nitrile ylides 44 and 47. 

Similarly, the transformation of alcohols to nitriles is a much sought after transformation, and a new procedure now allows the direct one-step conversion by the use of sodium cyanide-trimethylsilyl chloride and a catalytic amount of sodium iodide in dimethylformamide-acetonitrile. 

Treatment of primary aromatic amines with Ph3PBr2 to produce the imino-phosphorane followed by addition of an alkyl iodide provides a convenient monoalkylation procedure.The reagent system BusP-CCU-KCN-lS-crown-6 effects a simple one-pot conversion of primary alcohols to nitriles. Finally, PI3 deoxygenates sulphoxides, selenoxides, aldehyde oximes, and nitro-alkanes, and deprotects acetals and ketals. ... 

Ishida T, Watanabe H, Take T, Hamasaki A, Tokunaga M, Haruta M (2012) Metal oxide-catalyzed ammoxidation of alcohols to nitriles and promotion effect of gold nanoparticles for one-pot amide synthesis. Appl Catal A Gen 425 26 85-90... 

The txansformation of alcohols to nitriles actually involves three processes the oxidation of alcohols to aldehydes, the nitrogenation of the aldehydes, and the Schmidt/Beckmann rearrangement of the resulting iminodiazonium ion/aldoximes to nitriles (Scheme 4.7). Therefore, the primary task of optimization of reaction conditions is to develop nitrogen sources that are compatible with oxidants. 

Scheme 4.7 The general pathway for the ammoxidation of alcohols to nitriles...

Rokade BV, Malekar SK, Ptabhu KR (2012) A novel oxidative transfOTmation of alcohols to nitriles an efficient utihty of azides as a nitrogen source. Chem Commun 48(44) 5506—5508... 

Dighe SU, Chowdhury D, Batra S (2014) Iron nitrate/TEMPO a superior homogeneous catalyst for oxidation of primary alcohols to nitriles in air. Adv Synth Catal 356(18) 3892-3896... 

R C(OR )=NR , or their salts R C(OR )=NR X , respectively, has remained the method of choice for the synthesis of thionocarboxylates. > > <14-421 The starting materials can be obtained by addition of alcohols to nitriles, by alcoholysis of imido-chlorides, or by O-alkylation of amides. Dialkyl mono-(170) and bis-thiono-oxalates (171) are prepared in this way, in which case it is especially advantageous to use the imidates as free bases instead of their... 

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