3- substituted primary alcohol

Alcohols and alkyl halides are classified as primary secondary or tertiary according to the degree of substitution of the carbon that bears the functional group (Section 2 13) Thus primary alcohols and primary alkyl halides are compounds of the type RCH2G (where G is the functional group) secondary alcohols and secondary alkyl halides are compounds of the type R2CHG and tertiary alcohols and tertiary alkyl halides are com pounds of the type R3CG... 

Methyl-substituted primary alcohols can be separated after derivatization with [6-methoxy-2,5,7,8-tetramethylchromane-2-carboxylic acid] (Trolox M methyl ether) [13] while sec.- and tert.-alcohols are derivatized with 2-dimethylamino-l,3-dimethyl-octahydro-lf/-l,3,2-benzodiazaphosphole [14] (Eig. 7-5). 

The same process shown in Scheme 88 starting from different 2-substituted oxetanes and using biphenyl as the electron-carrier catalyst under THF reflux has been used to prepare regioselectively substituted primary alcohols. On the other hand, the combination of a DTBB-catalyzed ca 20%) lithiation with triethylaluminium in TFIF at —78 °C has been used for the transformation of strained oxetanes to substituted di- and triquinanes through a rearrangement process . An example is given in Scheme 89 for the transformation of oxetane 299 into the product 302 through radicals 300 and 301. 

The alcohol used for this ester is known as Alphanol 79 and is produced by the Oxo process. It consists of mixed normal primary and a-methyl substituted primary aliphatic C7. Cs. and Cs alcohols. 

Yield.—66% theoretical (30 gms.). Colourless plates with bluish fluorescence insoluble in water sparingly soluble in alcohol, ether, and carbon disulphide readily soluble in benzene M.P. 131°. (A., 215, 1.) Reaction LIV. (a) Condensation of Non-di-ortho-substituted-primary-... 

It is obvious that this method serves for the estimation of acetyl groups present in esters of alcohols or phenols. It also serves for the estimation of acetyl groups present in substituted primary or secondary amines. 

Use of triisobutylaluminum or diisobutylaluminum chloride results in a primary-alcohol (substitution by H, equation II). 

The particular set of equations written above is, of course, the SnI mechanism for substitution. Primary alcohols do not undergo rearrangement simply because they do not react by this mechanism. Instead, they react by the alternative Sn2 mechanism ... 

As already mentioned under acetyl chloride, add-chlorides react with alcohols, phenols, primary and secondary amines, the chlorine atom uniting with the hydrogen of the hydroxyl-, amido-, or imido-group, with the elimination of hydrochloric add, while the residues combine to form an ester or a substituted amide. The value of the Schotten-Baumann reaction depends on the fact that this reaction is so essentially facilitated by the presence of sodium hydroxide or potassium hydroxide- that even in the presence of water the decomposition takes place, which in the absence of alkalies is not possible ... 

Ley et al. have described the use of a combination of an oxidant, namely polymer-supported perruthenate 124, together with a reducing agent, namely polymer-supported cyanoborohydride 154. Readily available alcohols as primary feedstock were oxidized to intermediate 153 and further reacted with amines to afford more highly substituted amines, e.g., 155 (Scheme 29) [121]. 

Lipase (PsL)-mediated acylation reaction of a-methyl benzyl alcohol by vinyl acetate (Scheme 10.5) gives high enantioselectivity (E value 200) in [BMIM][Tf2N] than in methyl t r-butyl ether (MTBE) (E=4) at 55°C. At the boiling point of vinyl acetate, the E value was reduced to 150 from 200 [86, 87]. Similarly, lipase from Pseudomonas fluorescens (Lipase AK)-catalyzed enantioselective acylation of phosphate substituted primary alcohols in [BMIM][PF ] with enantioselectivity comparable to DIPE, though no selectivity was obtained in [BMIM][BF ] [87]. 

Hubaut et has studied the liquid phase hydrogenation of polyunsaturated hydrocarbons and carbonyl compounds over mixed copper-chromium oxides. The selectivity of monohydrogenation was almost 100 % for conjugated dienes but much lower for a,p-unsaturated carbonyls. This was due to the adsorption competition between the unsaturated carbonyls and alcohols as primary products. It was suggested that the hydrogenation site was an octahed-rally coordinated Cu ion with two anionic vacancies, and an attached hydride ion. The Cr ion in the same environment was probably the active site for side reactions (hydrodehydroxylation, nucleophilic substitution, bimolecular elimination). 

Ethylene glycol is the primary ingredient (up to 95%) in antifreeze. It is sometimes intentionally consumed as an alcohol substitute by alcoholics and is tempting to children because of its sweet taste. Intoxication by ethylene glycol itself causes inebriation and mild gastritis in addition, its metabolic products cause metabolic acidosis, renal failure, and death. Other glycols may also produce toxicity (Table 11-24). 

Ester shift changes Substituted Primary alcohol -... 

Since alkyl halides are extremely useful in synthesis, it is not surprising that chemists have devised several ways to prepare them from alcohols. For example, thionyl chloride (eq. 7.31) reacts with alcohols to give alkyl chlorides. The alcohol is first converted to a chlorosulfite ester intermediate, a step that converts the hydroxyl group into a good leaving group. This is followed by a nucleophilic substitution whose mechanism (Sj l or 5 2) depends on whether the alcohol is primary, secondary, or tertiary. 

In their recent work, Liang s group disclosed a convenient protocol for accessing complex pyrrole structures based on a transition metal-catalyzed SnI or SN2 -like substitution reaction of allylpropargylic alcohols with primary amine derivatives (Scheme 8.99) [294]. Thus, easily accessible l-en-4-yn-3-ols 272, upon Au(III)-... 

When 2-methyl-2-propanol tert-hvXyl alcohol, 65) is treated with concentrated HCl, 2-chloro-2-methylpropane (2-chloro-2-methylpropane ter -butyl chloride, 93) is isolated in 90% yield. Similarly, when 1-butanol (94) is treated with 48% HBr in the presence of sulfuric acid, a 95% yield of 1-bromobutane (96) is obtained. In both reactions, the oxygen of the alcohol reacts as a Br0nsted-Lowry base in the presence of the protonic acids, HCl, or sulfuric acid. The fact that alkyl halides are produced clearly indicates that these are substitution reactions. In previous sections, tertiary halides gave substitution reactions when a nucleophilic halide ion reacted by an Sfjl mechanism that involved ionization to a carbocation prior to reaction with the halide. Primary halides react with a nucleophilic halide ion by an 8 2 mechanism. It is reasonable to assume that tertiary alcohols and primary alcohols will react similarly, i/the OH unit is converted to a leaving group. 

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