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Nitrile From alcohol

Palladium-carbon hydrogen chloride Alcohols from nitriles... [Pg.66]

The imidazole nucleus is often found in biologically active molecules,3 and a large variety of methods have been employed for their synthesis.4 We recently needed to develop a more viable process for the preparation of kilogram quantities of 2,4-disubstituted imidazoles. The condensation of amidines, which are readily accessible from nitriles,5 with a-halo ketones has become a widely used method for the synthesis of 2,4-disubstituted imidazoles. A literature survey indicated that chloroform was the most commonly used solvent for this reaction.6 In addition to the use of a toxic solvent, yields of the reaction varied from poor to moderate, and column chromatography was often required for product isolation. Use of other solvents such as alcohols,7 DMF,8 and acetonitrile9 have also been utilized in this reaction, but yields are also frequently been reported as poor. [Pg.55]

The addition of dry HCl to a mixture of a nitrile and an alcohol in the absence of water leads to the hydrochloride salt of an imino ester (imino esters are also called imidates and imino ethers). This reaction is called the Pinner synthesisThe salt can be converted to the free imino ester by treatment with a weak base such as sodium bicarbonate, or it can be hydrolyzed with water and an acid catalyst to the corresponding carboxylic ester. If the latter is desired, water may be present from the beginning, in which case aqueous HCl can be used and the need for gaseous HCl is eliminated. Imino esters can also be prepared from nitriles with basic catalysts. ... [Pg.1183]

The addition of Grignard reagents to aldehydes, ketones, and esters is the basis for the synthesis of a wide variety of alcohols, and several examples are given in Scheme 7.3. Primary alcohols can be made from formaldehyde (Entry 1) or, with addition of two carbons, from ethylene oxide (Entry 2). Secondary alcohols are obtained from aldehydes (Entries 3 to 6) or formate esters (Entry 7). Tertiary alcohols can be made from esters (Entries 8 and 9) or ketones (Entry 10). Lactones give diols (Entry 11). Aldehydes can be prepared from trialkyl orthoformate esters (Entries 12 and 13). Ketones can be made from nitriles (Entries 14 and 15), pyridine-2-thiol esters (Entry 16), N-methoxy-A-methyl carboxamides (Entries 17 and 18), or anhydrides (Entry 19). Carboxylic acids are available by reaction with C02 (Entries 20 to 22). Amines can be prepared from imines (Entry 23). Two-step procedures that involve formation and dehydration of alcohols provide routes to certain alkenes (Entries 24 and 25). [Pg.638]

Moreover, the theories of the authors do not account for certain important features of their results that when the ratio [additive]/[AlCl3] is small, both the DP and the conductivity increase with increasing concentration of additive (alcohol, aldehyde, nitrile) and that with butyraldehyde the rate is markedly lower near the equivalence point where the DP is at a maximum, whereas in the alkyl halide-ethane mixtures both the rate and the DP went through a maximum at the same point. In our opinion the major part of these interesting results can be explained in the following terms, which coincide in part with the explanations given by the authors, but differ from theirs in two important respects. [Pg.78]

Chiral cyanohydrins are versatile intermediates in the synthesis of a-hydroxy acids, /3-amino alcohols, amino nitriles, a-hydroxy ketones and aziridines. For the synthesis of enantiopure cyanohydrins, the use of hydroxynitrile lyases is currently the most effective approach.Application of an organic-solvent-free system allows thermodynamically hindered substrates to be converted with moderate to excellent yields. With the use of the highly selective hydroxynitrile lyase from Manihot esculenta, the syntheses of several acetophenone cyanohydrins with excellent enantioselectivities were developed (Figure 8.2). (5)-Acetophenone cyanohydrin was synthesized on a preparative scale. ... [Pg.262]

Rajagopal et al. (1984) used numerous compounds to develop a proposed pathway of degradation of aldicarb in soil. These compounds included aldicarb oxime, A-hydroxymethyl aldicarb, A-hydroxymethyl aldicarb sulfoxide, A-demethyl aldicarb sulfoxide, A-demethyl aldicarb sulfone, aldicarb sulfoxide, aldicarb sulfone, A-hydroxymethyl aldicarb sulfone, aldicarb oxime sulfone, aldicarb sulfone aldehyde, aldicarb sulfone alcohol, aldicarb nitrile sulfone, aldicarb sulfone amide, aldicarb sulfone acid, aldicarb oxime sulfoxide, aldicarb sulfoxide aldehyde, aldicarb sulfoxide alcohol, aldicarb nitrile sulfoxide, aldicarb sulfoxide amide, aldicarb sulfoxide acid, elemental sulfur, carbon dioxide, and water. Mineralization was more rapid in aerobic surface soils than in either aerobic or anaerobic subsurface soils. In surface soils (30 cm depth) under aerobic conditions, half-lives ranged from 20 to 361 d. In subsurface soils (20 and 183 cm depths), half-lives under aerobic and anaerobic conditions were 131-233 and 223-1,130 d, respectively (Ou et al, 1985). The reported half-lives in soil ranged from approximately 70 d (Jury et ah, 1987) to several months (Jones et al, 1986). Bromilow et al. (1980) reported the half-life for aldicarb in soil to be 9.9 d at 15 °C and pH 6.34-7.0. [Pg.1545]

Amides from nitriles and alcohols in strong acids. General scheme ... [Pg.501]

OXAZOLINES FROM NITRILES AND AMINO ALCOHOLS, 385-386 OXAZOLINES FROM IMIDATES AND AMINO ALCOHOLS, 388-389 CONVERSION OF ALLYLIC ALCOHOLS TO P-AMINO ALCOHOLS VIA OXAZO-... [Pg.690]

The synthesis of ortho esters from nitriles is usually a two-step process involving first the formation of the imino ester hydrochloride and subsequent reaction with an alcohol. Several examples are described in Table I, even a glycol such as ethylene glycol can be used to obtain heterocyclic ortho esters, as shown in Eq. (11). [Pg.30]

Other routes to 1,3-oxazines employ condensation reactions between /3-chloroketones and nitriles or between chloroalkyl amides and alkynes <69LA(723)ill) (Scheme 62). Thiazines are available through similar condensations between thioamides, aldehydes and acetylenes (74G849), and AH- 1,3-benzoxazines may be prepared from 2-hydroxybenzyl alcohols and nitriles in the presence of either perchloric or sulfuric acids (Schemes 63 and 64) (68MIP22700). [Pg.1019]

The use of a cationic aza-Cope rearrangement in concert with a Mannich cyclization has also been applied to the total synthesis of enantiomerically pure (—)-crinine (359) (205). In the event, nucleophilic opening of cyclopentenoxide with the aluminum amide that was formed on reaction of (/ )-a-methylbenzyl-amine and trimethylaluminum gave the amino alcohol 485 together with its (15,25) diastereomer. Although there was essentially no asymmetric induction in this process, the diastereomeric amino alcohols were readily separated by chromatography, and the overall procedure therefore constitutes an efficient means for the preparation of enantiomerically pure 2-amino alcohols from epoxides. When the hydrochloride salt derived from 485 was treated with paraformaldehyde and potassium cyanide, the amino nitrile 486 was formed. Subsequent Swem oxida-... [Pg.342]

Esters can be made directly from nitriles by acid-catalysed reaction with the appropriate alcohol. Suggest a mechanism. [Pg.304]

Oxazincs are formed starting from nitriles and diols. 1,3-Amino alcohols react with phosgene or urea derivatives to give l,3-oxazin-2-ones. -Amino acids are converted to... [Pg.593]

Acid-catalyzed nucleophilic addition of a nitrile to a carbenium ion generated from alcohol (usually tertiary primary alcohols other than benzyl alcohol will not react), yielding an amide. Sanguigni, J.A. and Levine, R., Amides from nitriles and alcohols by the Ritter reaction, J. Med. Chem. 53, 573-574, 1964 Radzicka, A. and Konieczny, M., Studies on the Ritter reaction. I. Synthesis of 3-/5-bartbituryl/-Ipropanesulfonic acids with anti-inflammatory activity, ArcA Immunol. Ther. Exp. 30,421 32,1982 Van Emelen, K., De Wit, T., Hoomaert, G.J., and Compemolle, R, Diastereoselective intramolecular... [Pg.383]


See other pages where Nitrile From alcohol is mentioned: [Pg.69]    [Pg.69]    [Pg.111]    [Pg.67]    [Pg.1290]    [Pg.44]    [Pg.218]    [Pg.225]    [Pg.27]    [Pg.391]    [Pg.59]    [Pg.59]    [Pg.315]    [Pg.111]    [Pg.231]    [Pg.85]    [Pg.43]    [Pg.260]    [Pg.295]    [Pg.44]    [Pg.280]    [Pg.365]    [Pg.252]    [Pg.170]    [Pg.229]   
See also in sourсe #XX -- [ Pg.1644 ]




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From nitriles

Nitrile From alcohol, with inversion

Nitriles, preparation from alcohols

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