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Alcohols reagent compounds from

Outline practical syntheses of each of the following compounds from benzene alcohols and any necessary organic or inorganic reagents... [Pg.659]

Acidic Hydrolysis. Hydrolysis of esters by use of water and a mineral acid leads to an equiUbrium mixture of ester, alcohol, and free carboxyHc acid. Complete reaction can only be achieved by removal of alcohol or acid from the equiUbrium. Because esters have poor solubiUty in water, the reaction rate in dilute acids is fairly low. Therefore, emulsifiers such as sulfonated oleic acid or sulfonated aromatic compounds (TwitcheU reagent) are added to facihtate the reaction. [Pg.388]

In addition to the perfluoroalkylzinc compounds, the zinc reagent formed from 1,1,1-trifluorotrichloroethane has received considerable attention. This zinc compound was first reported as a stable ether complex [56]. Later, the DMF complex was isolated and the structure was determined by X-ray diffraction and shown to be monomeric [57] (equation 50). This zinc reagent undergoes a variety of functionalization reactions, and some typical examples are illustrated in Table 2 [47, 58, 59, 60, 61] The alcohol products (Table 2) can be converted to AiCF=CXCF3 (X = Cl, F) by further reaction with diethylaminosulfur trifluoride (DAST) and l,8-diazabicyclo[5 4.0]undec-7-ene (DBU) [60]... [Pg.681]

A closely related method does not require conversion of enantiomers to diastereomers but relies on the fact that (in principle, at least) enantiomers have different NMR spectra in a chiral solvent, or when mixed with a chiral molecule (in which case transient diastereomeric species may form). In such cases, the peaks may be separated enough to permit the proportions of enantiomers to be determined from their intensities. Another variation, which gives better results in many cases, is to use an achiral solvent but with the addition of a chiral lanthanide shift reagent such as tris[3-trifiuoroacetyl-Lanthanide shift reagents have the property of spreading NMR peaks of compounds with which they can form coordination compounds, for examples, alcohols, carbonyl compounds, amines, and so on. Chiral lanthanide shift reagents shift the peaks of the two enantiomers of many such compounds to different extents. [Pg.156]

The molybdenum-catalyzed cyclization procedure works well for a variety of homoprogargylic alcohols to afford the cycloisomeric 2,3-dihydrofuran compounds, as shown in Table I. The transformation was originally discovered with the reagent arising from reaction of molydbenum hexacarbonyl and trimethylamine oxide, but catalyst turnover and product isolation yields are significantly improved with the cunent procedure, which... [Pg.163]

Formylfuran reacts with potassium cyanide in alcohol solution to give a product containing two furan nuclei. What is this product and how does it form Can you suggest an alternative synthesis of the compound from 2-formylfuran using propane-1,3-dithiol as one reagent Hint consider an acyl anion equivalent approach). [Pg.95]

Problem 18.60 Synthesize the following compounds from alcohols of four or fewer C s, cyclohexanol and any needed solvents and inorganic reagents, (a) n-hexylamine, (h) triethylamine N-oxide, (c) 4-(N-methylamino)heptane, (d) cyclohexyldimethylamine, (e) cyclopentylamine, (/) 6-aminohexanoic acid. [Pg.435]

Halogenations with dihalotriphenylphosphoranes have been reviewed briefly by Fieser and Fieser.4 Dibromotriphenylphos-phorane appears to have been studied somewhat more than the dichloro compound, but both reagents effectively convert alcohols to alkyl halides, carboxylic acids and esters to acid halides, etc. The reaction of 1,2-epoxycyclohexane with dibromotriphenylphos-phorane under conditions similar to those described here gives a mixture of cis- and trans-1,2-dibromocyclohexanes. A reagent prepared from triphenylphosphine and carbon tetrachloride has been used for similar transformations.5... [Pg.66]

Amino alcohols can be prepared by treatment of an olefin with a reagent prepared from HgO and HBF4 along with aniline to give an aminomercurial compound... [Pg.832]

It is now generally admitted that this reaction involves both one-electron and two-electron transfer reactions. Carbonyl compounds are directly produced from the two-electron oxidation of alcohols by both Crvl- and Crv-oxo species, respectively transformed into CrIV and Crm species. Chromium(IV) species generate radicals by one-electron oxidation of alcohols and are responsible for the formation of cleavage by-products, e.g. benzyl alcohol and benzaldehyde from the oxidation of 1,2-diphenyl ethanol.294,295 The key step for carbonyl compound formation is the decomposition of the chromate ester resulting from the reaction of the alcohol with the Crvl-oxo reagent (equation 97).296... [Pg.351]

The starting compound 251 was reduced to 252 with sodium borohydride. The latter was heated under reflux in 6% sulfuric acid in methanol to afford compound 253. Treatment of the latter with maleic anhydride at 170° for 3 hr afforded compound 254. Bisdecarboxylation of 254 with dicarbonyl bistriphenylphosphinenickel in anhydrous diglyme under nitrogen at reflux temperature for 6 hr afforded the olefin 255 in 69% yield (171). The latter was reduced with lithium aluminium hydride to the primary alcohol 256, which was oxidized to the aldehyde 257 with Ar,A -dicyclohexylcarbodiimide, dimethyl sulfoxide and pyridine in dry benzene. Treatment of the aldehyde 257 with an excess of the Grignard reagent prepared from l-bromo-3-benzyloxybutane afforded a mixture of diastereoisomers represented by the structure 258. [Pg.170]

The compound is a 3° alcohol, conveniently made from a ketone and a Grignard reagent as shown. [Pg.328]


See other pages where Alcohols reagent compounds from is mentioned: [Pg.46]    [Pg.103]    [Pg.74]    [Pg.1069]    [Pg.206]    [Pg.69]    [Pg.170]    [Pg.229]    [Pg.61]    [Pg.214]    [Pg.286]    [Pg.214]    [Pg.254]    [Pg.207]    [Pg.125]    [Pg.47]    [Pg.125]    [Pg.1069]    [Pg.46]    [Pg.58]    [Pg.41]    [Pg.394]    [Pg.898]    [Pg.34]    [Pg.441]    [Pg.192]    [Pg.49]   
See also in sourсe #XX -- [ Pg.1511 , Pg.1512 ]




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Alcohols compounds

Alcohols reagents

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