Alcohols and diols

The rate law for oxidation of alkane diols by cerium(IV) in nitric acid media suggests formation of intermediate Ce(IV)-diol complexes. With substrates where the —OH groups are separated by five or more carbon 

Primary as well as secondary and tertiary alcohols are able to form carbonium ions in the presence of mineral acid catalysts. Thus, they can be used as starting materials in the Koch carboxylic acid syntheses [591, 601, 643-649]. These compounds can be reacted under pressure as well as under the conditions of the formic acid method. With but few exceptions the 

Starting material Olefins or alcoholes Temp. Yield of carboxylic acids (%)  

Cyclohexane Tert.-butanol 15-25 7 % Cg- and C7-acids, 54% Pivalic acid 0 

Methylcyclopentane tert. Butanol 15-25 46% 1-Methylcyclopentane-carboxylic acid-1 7 % Pivalic acid 

Methylcyclohexane tert. Butanol 15-25 72% 1-Methylcyclohexane-carboxylic acid-1 16% Pivalic acid 

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Various acetals and ketals from the reaction of alcohols and diols with aldehydes and ketones can be advantageously obtained using ion-exchange resin catalysts. Batch reactive distillation or DCR can be employed to obtain these acetals at high selectivity at very high conversion levels. 

A dispersant that can be used in drilling fluids, spacer fluids, cement slurries, completion fluids, and mixtures of drilling fluids and cement slurries controls the rheologic properties of and enhances the filtrate control in these fluids. The dispersant consists of polymers derived from monomeric residues, including low-molecular-weight olefins that may be sulfonated or phosphonated, unsaturated dicarboxylic acids, ethylenically unsaturated anhydrides, unsaturated aliphatic monocarboxylic acids, vinyl alcohols and diols, and sulfonated or phosphonated styrene. The sulfonic acid, phosphonic acid, and carboxylic acid groups on the polymers may be present in neutralized form as alkali metal or ammonium salts [192,193]. 

By using various polypyridyl oxo complexes a relationship between redox potentials ( 1/2) of the complexes and the efficiency and the selectivity of the electrocatalytic oxidation of alcohols and diols has been established.506 Higher 1/2 gives higher reactivity. The best results, from the point of view of synthesis, were obtained with the complex /ra ,v-[Ru (terpy)(0)2(0I I2)]2 which is characterized by a high redox potential and a relatively high stability. 

Transition-metal- and enzyme-catalyzed alkylations of ammonia and amines with alcohols and diols have been reviewed59. RuCl2(PPh3)3 is a homogeneous catalyst for the reaction of long-chain terminal alcohols with secondary amines to give tertiary amines (equation 22)60. 

Table 9.1). The rate of dehydrobromination from the intermediate bromoalkenes follows the pattern 2-bromoalkenes > Z-l-bromoalkenes > E- -bromoalkenes the corresponding chloro derivatives react more slowly. For optimum yield, the reaction temperature should be <100°C to reduce decomposition of the catalyst, and the concentration of base should be kept low to prevent isomerization of the resulting alkynes. [3-Elimination of HBr from 1,2-dibromo-1 -phenylethane can be controlled to yield 1-bromo-l-phenylethene in 83% yield [15]. The addition of alcohols and diols have a co-catalytic effect on the elimination reaction, as the alkoxide anions are transferred more effectively than the hydroxide ions into the organic phase [13]. 

Ferraboschi, P., Grisenti, P., Manzocchi, A. and Santaniello, E., Baker s yeast-mediated preparation of optically active aryl alcohols and diols for the s3mthesis of chiral hydroxy acids. 

In order to gain a better insight into these problems, a fundamental study of simple mono- and di-urethanes of the furan series was undertaken. This included the determination of their structure, properties and stability (35) and the mechanism and kinetics of their formation. The combinations investigated were furan alcohols and diols with aliphatic, aromatic and furanic isocyanates and the latter mono- and bis- derivatives with aliphatic and arylalkyl alcohols and diols. The furanic isocyanates prepared included 9 and those given below ... 

Mozhaev, V.V., Sergeeva, M.V. Belora, A.B. and Khmelnitsky, Y.L. (1990) Multipoint attachment to a support protects enzyme from inactivation by organic solvents -chymotrypsin in aqueous solutiuons of alcohols and diols. Biotechnol. Bioeng., 35, 653-659. 

Matthew, B.M. Anastasio, C. (2000) Determination of halogenated mono-alcohols and diols in water by gas chromatography with electron-capture detection. J. Chromatogr., 866, 65-77... 

Carbamates have been prepared by heating ethyl carbamate with a higherboiling alcohol in the presence or absence of catalysts [31-33], Aluminum iso-propoxide has been reported [34] to be an excellent catalyst for the interchange reaction between ethyl carbamate and benzyl alcohol. The interchange reaction is also effective for /V-alkyl carbamates as well as unsubstituted carbamates [35]. This catalyst is effective in preparing mono- and dicarbamates in excellent yields from primary and secondary alcohols and diols. Other effective catalysts are dibutyltin dilaurate [36], dibutyltin oxide [37], sulfuric acid or p-toluenesulfonic acid [31], and sodium metal (reacts with alcohols to give the alkoxide catalyst) [33]. 

Hydroxy-1,2-dicarboxylic acids, such as n- and L-a-hydroxysuccinic acid53 and D-tartaric acid.120 on treatment with sulfur tetrafluoride give complex mixtures of fluoroalkanes, fluoro-alkenes, fluoroalkyl fluorosulfites and cyclic five-membered ethers, derivatives of 2.2,5.5-tet-rafluorotetrahydrofuran. In the case of D-tartaric acid the cyclic ethers are predominant components (64%) of the reaction mixture.120 Linear and cyclic mono- and disulfites formed in these reactions give, after hydrolysis, the corresponding linear and cyclic polyfluoro alcohols and diols in high yield.53120... 

We, in most cases, have used a 2-meter column of polypropylene glycol (Ucon LB-550 X) on Celite 545 at 191° C. in helium flow and have succeeded in separating the aliphatic alcohols and diols. D. F. Percival s method (18) for separating diols from saponified polyesters should be adaptable to plasticizer analysis. 

A new ionic liquid, l-butyl-3-methylimidazolium tribromide can act as an oxidizing agent to convert alcohols to aldehydes and ketones.338 In the case of benzyl alcohols and diols, [Bmim][Br3] combines oxidizing and brominating properties in a one-pot synthesis of /3-bromoethyl esters. 

Sano, T. Ohashi, K. Oriyama, T. Remarkably fast acylation of alcohols with PhCOCl promoted by TMEDA. Synthesis 1999, 1141-1144. Carrigan, M. D. Freiberg, D. A. Smith, R. C. Zerth, H. M. Mohan, R. S. A simple and practical method for large-scale acetylation of alcohols and diols using Bi(OTf)3. Synthesis 2001, 2091-2094. 

The use of organometallic rhenium complexes has found a very broad scope as oxidation catalysts as described in the previous section, making MTO the catalyst of choice for many oxidation reactions of olefins. Interestingly, MTO and related rhenium compounds have also found application in the reverse reaction, the deoxygenation of alcohols and diols. Especially in recent years, this reaction has attracted much attention due to the increased interest in the use of biomass as feedstock for the chemical industry. This section provides an overview of the use of rhenium-based catalysts in the deoxygenation reaction of renewables. 

Q Use your knowledge of alcohol and diol reactions to propose mechanisms and products for similar reactions that are new. 

Backvall et al. [10] have recently reported substantial improvements in the described process. A range of 1 -phenylethanol derivatives can be synthesized from the raeemates in excellent yields and >99 % ee by using a binuclear ruthenium complex combined with an immobilized lipase and a specifically designed acyl donor (4-Cl-PhOAc). Even aliphatic alcohols and diols... 

These results in Table I can be explained by reactions in Scheme 2. As shown in Figures 2b and 2c, peaks at 1270 cm due to C-O stretching band in conjugated ester disappeared, while peaks at 1730 cm due to ester C=0 groups remained. These results indicate that the transesterification proceeded in the presence of alcohols and diols. In case of diol, the transesterification at both ends would afford re-crosslinking. A similar trend was observed for other difunctional additives such as diamine and amino acid. When amino compounds were added, recovered polymers had a peak at 1700 cm as shown in Figures 2d and 2e due to cyclic imide moieties. 

Lipase-catalyzed asymmetric hydrolysis has also been conducted on numerous monocyclic, variously substituted five-, six-, and seven-membered cycloalkane and cycloalkene secondary alcohols and diols. More recent reports include cis-4-acetoxyflavan, substituted cyclopentenones, and the 1,2-bis(hydroxymethyl)cyclobutanol derivative exemplified in eq 3. ... 

Methylene acetals. Methylene acetals are obtained in good yield by the reaction of alcohols and diols with DMSO and N-bromosuccinimidc or N-chlorosuccinimide. For example, cyclohexanol (l)in dry DMSO containing 1-2 molar eq. ofNBS is heated at 50° with stirring overnight. After workup, dicyclohexyloxymethane (2) is obtained in 80 yield. 

Kobayashi et al. developed chiral Lewis acids derived from A -benzyldiphenylproli-nol and boron tribromide and used these successfully as catalysts in enantioselective Diels-Alder reactions [89]. The corresponding polymeric catalyst 71 was prepared and used for the Diels-Alder reaction of cyclopentadiene with methacrolein [90]. Different polymeric catalysts 72, 73, 74 were prepared from supported chiral amino alcohols and diols fimctionalized with boron, aluminum and titanium [88,90]. In these polymers copolymerization of styrene with a chiral auxiliary containing two polymerizable groups is a new approach to the preparation of crosslinked chiral polymeric ligands. This chiral monomer unit acts as chiral ligand and as a crosslink. 

Eichler B. and Schink B. (1986) Fermentation of primary alcohols and diols, and pure culture of syntrophicaUy alcohol-oxidizing anaerobes. Arch. Microbiol. 143, 60-66. 

Racemic or chiral p-amino alcohols and diols were coupled with methyl difluoro(diethoxyphosphono)dithioacetate to give the corresponding p-hy-droxythioaminides. These intermediates were then cyclised under Mitsunobu conditions in the presence of either 6-chloropurine or 3-benzoylthymine to yield nucleosidic base-derived thiazolines linked to a difluoromethylphosphonate diester (88a, b). 

This phase can be used in the preparative and analytical stereochemical resolution of a wide variety of compounds, including acetate derivatives of alcohols and diols benzylic alcohol derivatives pora-substituted d-phenyl-d-valerolactones 3,4-dihydro-2H-pyran-2-carboxylic acid derivatives phenylvinylsulfoxide fra s-stilbene oxide (46). 

Summary The use of readily available norbornylsilanes as protecting groups for alcohols and diols is reported. Stabilities of exemplary norbomylsilyl conq>ounds toward various reagents and deprotection conditions are conq>ared with tert-butyldimethylsilyl-, iso-propyldimethyl, and trimethylsilyl groups. The norbomyl-substituted compounds have been found to be more stable than the corresponding o-propyl derivatives. 

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