Alcohols Organic Syntheses procedures

In addition, an Organic Synthesis procedure of preparing aziridine from P-amino alcohol exists. ... 

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. ... 

The procedure described is essentially that of Shioiri and Yamada. Diphenyl phosphorazidate is a useful and versatile reagent in organic synthesis. It has been used for racemlzatlon-free peptide syntheses, thiol ester synthesis, a modified Curtius reaction, an esterification of a-substituted carboxylic acld, formation of diketoplperazines, alkyl azide synthesis, phosphorylation of alcohols and amines,and polymerization of amino acids and peptides. - Furthermore, diphenyl phosphorazidate acts as a nitrene source and as a 1,3-dipole.An example in the ring contraction of cyclic ketones to form cycloalkanecarboxylic acids is presented in the next procedure, this volume. 

The synthesis of sulfosuccinate esters—either monoesters or diesters—or the corresponding amides is usually done in a two-step procedure. In both cases, the MA is reacted in the first step with organic alcohol, organic amine, or (in the case of monoesters) with other suitable organic reactants that bear hydroxyl (or even protic) groups in the second step sulfation of the maleic ester takes place. 

The use of ester-cleaving enzymes is probably going to be one of the most useful biological-chemical methods in the synthetic laboratory. No example of this type of reaction has hitherto been published in the Organic Syntheses series of procedures. So far, the only biological-chemical Organic Synfheses-procedures are two yeast reductions,4 5 one oxidation with horse-liver-alcohol-dehydrogenase,6 and a disaccharide synthesis catalyzed by emulsin.7 The procedure described here is... 

Although Cr03 is soluble in some organic solvents, like tert-butyl alcohol, pyridine or acetic anhydride, its use in such solvents is limited, because of the tendency of the resulting solutions to explode.2,3 Nevertheless, acetone can safely be mixed with a solution of chromium trioxide in diluted aqueous sulfuric acid. This useful property prompted the development of the so-called Jones oxidation, in which a solution of chromium trioxide in diluted sulfuric acid is dropped on a solution of an organic compound in acetone. This reaction, first described by Jones,13 has become one of the most employed procedures for the oxidation of alcohols, and represents a seminal contribution that prompted the development of other chromium (VI) oxidants in organic synthesis. 

The corresponding silyl ethers are stable under the usual conditions employed in organic synthesis for the deprotection of silyl groups and were deprotected using photolysis at 254 nm in yields ranging from 62-95%. Therefore, the hydrosilylation of ketones and aldehydes followed by this deprotection procedure is formally equivalent to the reduction of carbonyl moieties to the corresponding alcohols. 

The addition of an organomagnesium compound to an aldehyde is an excellent general method for preparing secondary alcohols, and the side-reactions referred to above are a problem only in particularly unfavourable cases. Large numbers of examples have been tabulated [A] and examples from Organic Synthesis are listed in Table 6.1. a,[3-Unsaturated aldehydes normally undergo mainly or exclusively 1,2-addition, as in the examples in Table 6.1. The following experimental procedure is typical. 

Isoxazolines are used in organic synthesis because they mask a number of functionalities such as p-hydroxyketones or y- or P-amino alcohols. While they are not affected by the reaction conditions of many organic transformations, they can be easily unmasked in later steps of the synthesis. In fact, because of its wide applicability, this cycloaddition-reductive opening procedure has been termed the "isoxazoline route". 

A procedure for the cathodic reduction of anthranilic acid to the corresponding alcohol is described in Organic Synthesis [36]. Because the carboxylic acid group is so difficult to reduce, the method cannot normally be used for acid substituted with easily reducible functions or groups. For instance, pentafluorobenzoic acid loses fluorine by cathodic cleavage at mercury, in 20% sulfuric acid, at —1.20 V (SCE) 2,3,5,6-tetrafluor-obenzoic acid is obtained in 75% yield [38]. However, at potentials more negative than... 

The generation of a quaternary carbon center is not a trivial undertaking in organic synthesis. Multiple synthetic steps are often required to generate a quaternary carbon. The high-yield formation of both alcohols and vicinal diols by a one-pot procedure with the concomitant formation of a quaternary carbon center was recently reported [19]. 

This asymmetric epoxidation technology affords high yields and enantiose-lectivities with a broad range of allylic alcohol substrates, and has been widely applied in organic synthesis [34-38], The original procedure [33] required stoichiometric amounts of the titanium tartrate (titanium is a rather unreactive epoxidation catalyst) but was subsequently improved to the extent that 5-10 wt.% is sufficient. 

Peptide synthesis. Introduced by Bergmann and Zervas in 1932 for the protection of amino groups in peptide synthesis, the reagent (CbCl) still affords probably the most widely used means of N-protection. Preparation from benzyl alcohol and phosgene. A procedure stated to give better material than the Organic Syntheses procedure is described by Katchalski. ... 

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