Alkenes => alcohols

Faraday, in 1834, was the first to encounter Kolbe-electrolysis, when he studied the electrolysis of an aqueous acetate solution [1], However, it was Kolbe, in 1849, who recognized the reaction and applied it to the synthesis of a number of hydrocarbons [2]. Thereby the name of the reaction originated. Later on Wurtz demonstrated that unsymmetrical coupling products could be prepared by coelectrolysis of two different alkanoates [3]. Difficulties in the coupling of dicarboxylic acids were overcome by Crum-Brown and Walker, when they electrolysed the half esters of the diacids instead [4]. This way a simple route to useful long chain l,n-dicarboxylic acids was developed. In some cases the Kolbe dimerization failed and alkenes, alcohols or esters became the main products. The formation of alcohols by anodic oxidation of carboxylates in water was called the Hofer-Moest reaction [5]. Further applications and limitations were afterwards foimd by Fichter [6]. Weedon extensively applied the Kolbe reaction to the synthesis of rare fatty acids and similar natural products [7]. Later on key features of the mechanism were worked out by Eberson [8] and Utley [9] from the point of view of organic chemists and by Conway [10] from the point of view of a physical chemist. In Germany [11], Russia [12], and Japan [13] Kolbe electrolysis of adipic halfesters has been scaled up to a technical process. 

Three other all-atom force fields have also received much recent attention in the literature MMFF94 [36-40], AMBER94 [9] and OPLS-AA [41, 42] and are becoming widely used. The latter two force fields both use non-bonded parameters which have been adjusted in order to reproduce experimental liquid phase densities and heats of vaporisation of small organic molecules. For example, OPLS-AA includes calculations on alkanes, alkenes, alcohols. 

Section Title Alkyne-Alkyne Carboxylic acid-Alcohol Ether-Alkene Halide-Halide Halide-Halide Alcohol-Ester Alcohol-Ester Ester-Alkene Ester-Alkene Alcohol-Ether Alcohol-Oxide... 

In the absence of alkene, alcohols lose hydrogen to the Ti—H202 complex to form water and ketone or aldehyde as shown in Fig. 6—IO47,49... 

The Fischer-Tropsch reaction has now been known for almost 70 years and is of great importance partly for itself and also as part of a coupled set of processes whereby steam or oxygen plus coal or coke is transformed into methane, alkenes, alcohols, and gasolines. According to Eqs.I-IV in the most... 

Using dicyclohexyl-18-crown-6 it is possible to dissolve potassium hydroxide in benzene at a concentration which exceeds 0.15 mol dm-3 (Pedersen, 1967). The free OH- has been shown to be an excellent reagent for ester hydrolysis under such conditions. The related solubilization of potassium permanganate in benzene, to yield purple benzene , enables oxidations to be performed in this solvent (Hiraoka, 1982). Thus, it is possible to oxidize a range of alkenes, alcohols, aldehydes, and alkylbenzenes under mild conditions using this solubilized reagent. For example, purple benzene will oxidize many alkenes or alcohols virtually instantaneously at room temperature to yield the corresponding carboxylic acids in near-quantitative yields (Sam Simmons, 1972). 

The readsorption and incorporation of reaction products such as 1-alkenes, alcohols, and aldehydes followed by subsequent chain growth is a remarkable property of Fischer-Tropsch (FT) synthesis. Therefore, a large number of co-feeding experiments are discussed in detail in order to contribute to the elucidation of the reaction mechanism. Great interest was focused on co-feeding CH2N2, which on the catalyst surface dissociates to CH2 and dinitrogen. Furthermore, interest was focused on the selectivity of branched hydrocarbons and on the promoter effect of alkali on product distribution. All these effects are discussed in detail on the basis... 

In Fischer-Tropsch synthesis the readsorption and incorporation of 1-alkenes, alcohols, and aldehydes and their subsequent chain growth play an important role on product distribution. Therefore, it is very useful to study these reactions in the presence of co-fed 13C- or 14 C-labeled compounds in an effort to obtain data helpful to elucidate the reaction mechanism. It has been shown that co-feeding of CF12N2, which dissociates toward CF12 and N2 on the catalyst surface, has led to the sound interpretation that the bimodal carbon number distribution is caused by superposition of two incompatible mechanisms. The distribution characterized by the lower growth probability is assigned to the CH2 insertion mechanism. 

The Fischer-Tropsch synthesis, which may be broadly defined as the reductive polymerization of carbon monoxide, can be schematically represented as shown in Eq. (1). The CHO products in Eq. (1) are any organic molecules containing carbon, hydrogen, and oxygen which are stable under the reaction conditions employed in the synthesis. With most heterogeneous catalysts the primary products of the reaction are straight-chain alkanes, while the secondary products include branched-chain hydrocarbons, alkenes, alcohols, aldehydes, and carboxylic acids. The distribution of the various products depends on both the type of catalyst and the reaction conditions employed (4). 

It is now superflous to point out the renewed interest for the Fischer-Tropsch (F-T) synthesis (j) i. . the conversion of CO+H2 mixtures into a broad range of products including alkanes, alkenes, alcohols. Recent reviews (292.9k ) emphasized the central problem in F-T synthesis1 selectivity or more precisely chain-length control. 

The pyridine ylide method also allows determination of the rate constants for the intermolecular reactions of carbenes with alkenes, alcohols, or other carbene... 

If a sample contains one or more members of a homologous series, identifications can be made using a plot of log tR against the number of carbon atoms, previously prepared from standards. The plot, which is valid for one temperature only, is linear and can be used for alkanes, alkenes, alcohols, aldehydes, ketones, esters and ethers. 

The OPLS parameters (charges and Lennard-Jones terms) were obtained primarily via Monte Carlo simulations with particular emphasis on reproducing the experimental densities and heats of vaporization of liquids. Those simulations were performed iteratively as part of the parametrization, so better agreement with experiment is obtained than in previous studies where the simulations were usually carried out after the parametrization. Once the OPLS parametrization was completed, further simulations were also performed in order to test the new set of parameters in the calculation of other thermodynamic and structural properties of the system, besides its density and its heat of vaporization. Parameters have now been generated, among others, for water, alkanes, alkenes, alcohols, amides, alkyl chlorides, amines, carboxylic esters and acids, various sulfur and nitrogen compounds, and nitriles. A protein force field has been established as well. 

In a similar way other molecules such as H2) CO, 02, NO, alkenes, alcohols become adsorbed, e.g.,... 

It is a useful oxidant for hydrocarbons, alkenes, alcohols and aldehydes. Permanganate reacts with carbon-carbon double bonds to form a cyclic manganate(V) diester. The nature of the products is determined by subsequent rapid processes. 

The other acetogenins, shown in Table II, are a varied assortment of small molecule compounds which as a group contain alkene, alcohol, and carbonyl (acid, ester, aldehyde, and ketone) functionality. They are fairly typical substances with common structural features. Again, those compounds possessing an odd number of carbon atoms are less common, and biogenetlcally may be derived from a propionate starter unit. 

A similar approach can be used for estimating rate constants with a variety of other organics such as alkenes, alcohols, and nitrates, although the agreement is not as good in many cases (Kwok and Atkinson, 1995). 

Alkylation with Alkanes. Alkylation of aromatic hydrocarbons with alkanes, although possible, is more difficult than with other alkylating agents (alkyl halides, alkenes, alcohols, etc.).178 This is due to the unfavorable thermodynamics of the reaction in which hydrogen must be oxidatively removed. 

Sulfation is the generation of an oxygen sulfur(IV) bond, where the oxygen is attached to the carbon backbone, in the most controlled manner possible, using some form of sulfur dioxide moiety. When sulfating alcohols, the reaction is strongly exothermic, Examples of feedstocks for such a process include alkenes, alcohols, or phenols. Unlike the sulfonates, which exhibit excellent stability to hydrolysis, the alcohol sulfates are readily susceptible to hydrolysis in acidic media, The sulfation of fatty alcohols and fatty polyalkoxylates has produced a substantial body of commercial detergents and emulsifiers. 

Aromatic compounds are usually readily alkylated or acylated by a Friedel-Crafts reaction.150 The combination of reagents used most commonly for aromatic alkylation is an alkyl halide with a strong Lewis acid (Equation 7.65). However, alkenes, alcohols, mercaptans, and a number of other types of organic... 

The conventional resinsulfonic acids such as sulfonated polystyrenes (Dowex-50, Amberlite IR-112, and Permutit Q) are of moderate acidity with limited thermal stability. Therefore, they can be used only to catalyze alkylation of relatively reactive aromatic compounds (like phenol) with alkenes, alcohols, and alkyl halides. Nafion-H, however, has been found to be a suitable superacid catalyst in the 110-190°C temperature range to alkylate benzene with ethylene (vide infra) 16 Furthermore, various solid acid catalysts (ZSM-5, zeolite /3, MCM-22) are applied in industrial ethylbenzene technologies in the vapor phase.177... 

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