Tertiary 3 Alcohols

The order of reactivity of the hydrogen halides parallels their acidity HI > HBr > HCl >> HF Hydrogen iodide is used infrequently however and the reaction of alco hols with hydrogen fluoride is not a useful method for the preparation of alkyl fluorides Among the various classes of alcohols tertiary alcohols are observed to be the most reactive and primary alcohols the least reactive... 

AC2O, Pyr, 20°, 12 h, 100% yield. This is one of the most common methods for acetate introduction. By running the reaction at lower temperatures good selectivity pan be achieved for primary alcohols over secondary alcohols. Tertiary alcohols are generally not acylated under these conditions. 

Miller and Kirchner [9] and Mathis and Ourisson [1] have both already demonstrated that esterification at the start can be employed to distinguish primary, secondary and tertiary alcohols. Tertiary alcohols react much more slowly... 

Among the various classes of alcohols, tertiary alcohols are observed to be the most reactive and primary alcohols the least reactive. 

Suitable starting materials for the Mitsunobu reaction are primary and secondary alcohols. Tertiary alcohols are less suitable since these are bad substrates for a SN2-mechanism. 

Note that in the S l reaction, which is often carried out under acidic conditions, neutral water can act as a leaving group. This occurs, for example, when an alkyl halide is prepared from a tertiary alcohol by reaction with HBr or HC1 (Section 10.6). The alcohol is first protonated and then spontaneously loses H2O to generate a carbocation, which reacts with halide ion to give the alkyl halide (Figure 11.13). Knowing that an SN1 reaction is involved in the conversion of alcohols to alkyl halides explains why the reaction works well only for tertiary alcohols. Tertiary alcohols react fastest because they give the most stable carbocation intermediates. 

Tertiary Alkyl Alcohols. Tertiary alkyl alcohols generally undergo facile reduction when treated with acids in the presence of organosilicon hydrides.127,136 This comparative ease of reduction reflects the enhanced stability and ease of formation of tertiary alkyl carbenium ions compared with primary and secondary carbenium ions. Thus, treatment of 1-methylcyclohexanol with mixtures of triethylsilane and aluminum chloride in dichloromethane produces near quantitative yields of methylcyclohexane with or without added hydrogen chloride in as little as 30 minutes at room temperature, in contrast to the more vigorous conditions needed for the reduction of the secondary alcohol cyclohex-anol.136... 

Aromatic alcohols, tertiary arylalkyl-carbinols and trans-2 -arylcyclohexanols R,R-N-DNP-DPEDA Isopropanol and n-heptane mixtures 182... 

High purity isobutylene is used in numerous applications beside the polyisobutylene just mentioned butyl rubber, 0x0 alcohols, tertiary butyl alcohols, di- and tri-isobutylene and methyl methacrylate. 

Many transition-metal complexes have been reported as catalysts of this reaction, including [lr(g-Cl)(coe)2]2 [74] and [lrH2(solv.)(PPh3)][SbF6] [75]. The latter catalyst appeared to be a very active and highly selective. The hydroxyl group can be selectively silylated, even in the presence of other potentially reactive C=C and C=0 groups. The order of relative reactivities of alcohol isomers is secondary alcohol > primary alcohol > tertiary alcohol. 

Sulfur Compounds—Other Significant Sulfur Hexafluoride Technetium Tertiary Alcohols Tertiary Amines (Alkyl, Aryl)... 

Delta-1,8-Terpodiene Teriary Butyl Alcohol Tertiary Butyl Hydroperoxide 2,4,5-T(Esters)... 

In contrast to the primary alcohols, tertiary alcohols eliminate water smoothly at 0°C in the presence of a 2-10 molar excess of hydrogen fluoride followed by polymerization.259 Reduced polymerization and satisfying yields of tertiary alkyl fluorides are achieved only at low temperatures (— 50 C). The reactivity of secondary aliphatic alcohols is thus interpreted to be between the other two types. High yields of alkyl fluorides are difficult to obtain because of the competing reactions and the effect of temperature on the equilibrium. 

Alcohols such as methanol, 2-propanol, and benzhydrol are cleanly oxidized to the corresponding carbonyl compounds upon photoexcitation with Na3PWi2O40 in water or with (n-P NfoPW C in CH3CN (406). The quantum yields appear to be governed by the oxidation potential of the alcohol, the availability of a-hydrogens, and the tightness of complexation with the photocatalyst The reactivity order is primary alcohol > secondary alcohol > tertiary alcohol. 

A number of Lewis base adducts of diorganosilylenes have been observed by electronic spectroscopy in frozen matrices (see Section V.A)115. The silylene-donor adducts of ethers, tertiary alcohols, tertiary amines and sulfides were found to revert to silylenes upon warming, but primary and secondary alcohol adducts underwent rearrangement to the H—O formal insertion products (equation 55). 

The observed reactivity gradation for this type of reaction is for the acid HI > HBr > HC1 > HF, and for the alcohols tertiary > secondary > primary. 

Synonyms Trimethylcarbinol, Tertiary isobutyl alcohol, Tertiary butyl alcohol. 

TERTIARY BUTYL ALCOHOL (see Alcohol,Tertiary Butyl)... 

Tertiary alcohols, tertiary ethers, or carboxylic acid esters of tertiary alcohols can undergo El eliminations, but only in the presence of Bronsted or Lewis acids. Anyone who has prepared a tertiary alkoxide by a Grignard reaction and treated the crude reaction mixture with HC1 and obtained the alkene knows that tertiary alcohols can be converted into alkenes even with dilute hydrochloric acid. 

Primary alcohol Secondary alcohol Tertiary alcohol Phenol... 

In terms of functional group compatibility, ethers, alcohols, tertiary amines, acetals, esters, amides and heterocycles are compatible with the Pauson-Khand reaction. In the intramolecular version, relatively few carbon skeletons undergo the cyclization. Most intramolecular PKRs use systems derived from hept-l-en-6-yne (6) or propargyl allyl ethers (7) or amines (8). Other interesting and more recent substrates are enynes connected through aromatic rings like 9-11, which have allowed us and other groups to obtain aromatic polycycles (Fig. 1) [28-31]. 

While tertiary alcohols, tertiary steroidal alcohols " and many benzylic alcohols - are converted smoothly to the fluorinated products, secondary substrates need more severe reaction conditions and primary alcohols do not give the reaction at all. An Organic Synthesis procedure for the preparation of the reagent and its application to the synthesis of 1-fluoro-adamantane has been published examples of fluorides 1 formed using this procedure are given. ... 

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