Olefinic alcohols from acetylenic acids

Developments in the production of acetaldehyde from acetylene have focussed attention on this reaction. Alcohols may also be formed from olefines. Sulphuric acid (20—4 5%), phosphoric acid 30—35%), or acetic acid (96%), in presence of a mercury salt may be employed. Selenium dioxide has been used for a similar purpose. (J. C. S., 1932, 2342.) See also, A. C. R 1934,123. 

Anodic dehydrogenations, e.g., oxidations of alcohols to ketones, have been treated in Sect. 8.1 and formation of olefins by anodic elimination of C02 and H+ from carboxylic acids was covered in Sect. 9.1. Therefore this section is only concerned with anodic bisdecarboxylations of v/odicarboxylic acids to olefins. This method gives usually good results when its chemical equivalent, the lead tetraacetate decarboxylation, fails. Combination of bisdecarboxylation with the Diels-Alder reaction or [2.2] -photosensitized cycloadditions provides useful synthetic sequences, since in this way the equivalent of acetylene can be introduced in cycloadditions. 

Hydrides from carboxylic acids Carboxylic acids from hydrides Carboxylic acids from hydrides Esters from hydrides Hydrides from aldehydes Hydrides from aldehydes Alkyls from aldehydes Ketones from methylenes Ketones from ketones Alkyls from olefins Acetylenes from halides also acetylenes from acetylenes Esters from alcohols also esters from carboxylic acids Alkyls from olefins Alkyls from olefins... 

Examples of alkylation, dealkylation, homologation, isomerization, and transposition are found in Sections 1, 17, 33, and so on, lying close to a diagonal of the index. These sections correspond to such topics as the preparation of acetylenes from acetylenes carboxylic acids from carboxylic acids and alcohols, thiols, and phenols from alcohols, thiols, and phenols. Alkylations that involve conjugate additions across a double bond are found in Section 74 (alkyls, methylenes, and aryls from olefins). 

Similarly, a C-aryl heptose sugar is prepared for the first time from the diol obtained from ascorbic acid. The epoxide (40), made from the diol (39), on reaction with acetylenic anion and further transformations gave the olefinic alcohol (42). Sharpless epoxidation of 42 and cyclization furnished the C-aryl heptose sugars (43a and 43b) in an efficient way (Scheme 22.10). 

This was the appearance of publications by W. Reppe and co-workers in followed by Badische Anilin und Soda Fabrik patents/ They showed that various triphenylphosphine complexes of nickel, especially [Ni(CO)2(PPh5)2](Ph = QHs), were more effective than other nickel complex catalysts for the polymerization of olefinic and acetylenic substances and that others, especially [NiBr2(PPh3)2], catalyzed the formation of acrylic acid esters from alcohols (ROH), acetylene, and carbon monoxide ... 

Aminoalcohols can be used for Friedel-Crafts syntheses with remarkable efficiency . Alcohols and acids have been prepared and olefins synthesized from terminal acetylene derivatives via gc/n-diboro compounds . 

Actual operating capacities of Reppe carbonylation processes are difficult to estimate since only a few data are available in the literature. However, it is known that some of the syntheses are carried out on an industrial scale, e. g. the synthesis of acrylates from acetylene, carbon monoxide and alcohols (BASF) [1004, 1005], the acetic acid synthesis from methanol and carbon monoxide and the synthesis of higher molecular weight saturated carboxylic acids from olefins, carbon monoxide and water. Propionic acid (30,000 tons/year) and to a smaller extent heptadecanoic dicarboxylic acid are manufactured via the carbonylation route at BASF. Butanol is made from propylene in Japan [1003, 1004]. 

Palladium(ii) complexes of trimethylsilyl enol ethers derived from ketones can be carbonylated (50 atm. CO) in the presence of an alcohol to give /S-keto-esters only three examples are quoted in this preliminary report. a, -Unsatur-ated esters can be converted into -keto-esters in ca. 70% yields using Na2PdCl4 in aqueous acetic acid containing t-butyl hydroperoxide or hydrogen peroxide. This method may be inappropriate if the starting ester contains other olefinic (and presumably acetylenic) bonds as these will probably also be attacked. 

Z-Trisubstituted allylic alcohols are obtained from protected a-hydroxy-ketones in a lithium-free Wittig reaction and 1-bromo-olefins (and hence acetylenes) are produced from the reaction of Ph3P=CHBr with aldehydes. References to two syntheses of substituted-allenes have appeared Ph3P=C(R )C02R and R R C=C=0 (generated in situ from the acid chloride... 

Despite the chemical diversity of the several hundred structures representing herbicidal activity, most reactions of herbicides fall within only a limited number of mechanistic types oxidation, reduction, nucleophilic displacements (such as hydrolysis), eliminations, and additions. "Herbicides", after all, are more-or-less ordinary chemicals, and their principal transformations in the environment are fundamentally no different from those in laboratory glassware. Figure 2 illustrates three typical examples which have received their share of classical laboratory study—the alkaline hydrolysis of a carboxylic ester (in this case, an ester of 2,4-dichlorophenoxyacetic acid, IX), the cycloaddition of an alcohol to an olefin (as in the acetylene, VI), and the 3-elimination of a dithiocarbamate which provides the usual synthetic route to an isothiocyanate (conversion of an N.N-dimethylcarbamic acid salt, XI, to methyl isothiocyanate). Allow the starting materials herbicidal action (which they have), give them names such as "2,4-D ester" or "pronamide" or "Vapam", and let soil form the walls of an outdoor reaction kettle the reactions and products remain the same. 

Classification and Organization of Reactions Forming Difunctional Compounds. This chapter considers all possible difunctional compounds formed from the groups acetylene, carboxylic acid, alcohol, thiol, aldehyde, amide, amine, ester, ether, epoxide, thioether, halide, ketone, nitrile, and olefin. Reactions that form difunctional compounds are classified into sections on the basis of the two functional groups of the product. The relative positions... 

There is a relatively meagre choice of methods suitable for partial reduction of acetylene and its derivatives. In individual cases partial reduction can be effected with sodium and alcohols, zinc and glacial acetic acid, or the zinc-copper couple (cf. a review by Campbell and Campbell253). Partial reduction of the triple bond in acetylene itself was described as early as 1916 by Traube and Passarge254 who used chromium(n) chloride. A variation of this process, in which chromium(n) sulfate is used in water or aqueous dimethylformamide, has been used recently with considerable success for preparation of trans-olefins from various compounds containing C=C bonds 255 formation of by-products or conversion into m-ethylenes was not observed with this method. 

The classification is unaffected by allylic, vinylic, or acetylenic unsaturation appearing in both starting material and product, or by increases or decreases in the length of carbon chains for example, the reactions t-BuOH - f-BuCOOH, PhCHaOH - PhCOOH, and PhCH=CHCH20H PhCH=CHCOOH would all be considered as preparations of carboxylic acids from alcohols. Conjugate reduction and alkylation of unsaturated ketones, aldehydes, esters, acids, and nitriles have been placed in category 74 (alkyls from olefins). 

Walter Reppe also used his new base to expand the chemistry of acetylene. His first major breakthrough, in the summer of 1939, was the addition of carbon monoxide to acetylene in the presence of alcohols (or water) and a nickel catalyst to form acrylates. Carbon monoxide had attracted attention for many years as a readily available, cheap and reactive carbon compound. I.G. Farben employed it in the Pier methanol synthesis, Ruhrchemie used it in the Fischer-Tropsch synthetic petrol process, and Du Pont had carried out research on the addition of carbon monoxide to olefins at very high pressure and temperatures. Additional impetus for the use of carbon monoxide in acetylene chemistry was provided by the introduction of covered carbide furnaces at I.G. Farben s Knapsack plant in 1938, which permitted the collection of by-product carbon monoxide. The polymers of acrylic esters were already used for treating leather and for paint, but acrylic acid was made from ethylene oxide, and consequently was rather expensive. Reppe s process reached the pilot plant stage by 1945, and was subsequently used on a large scale by BASF and its American partners. 

Bromination of jojoba oil in carbon tetrachloride yielded tetrabromojojoba derivatives at 20°C (9). When treated with excess base, these bromides yielded the corresponding acetylenes from Z,Z olefins of jojoba or allenes from the E,E isomerized jojoba (Scheme 2) with the expected hydrolysis to acid and alcohol. Allylic bromination (nonregiospecific) with A-bromosuccsinimide (NBS) followed by dehydro-halogenation yielded polyunsaturated oils with degrees of unsaturation up to the hexaenoic jojoba derivative (10). These highly unsaturated materials were envisioned... 

A convenient stereospecific synthesis under mild conditions of terminal acetylenes from olefins via the treatment of lithium ethynyl-trialkylborates with iodine has recently been published. Carboxyl groups, including sterically hindered ones and those of a-amino acids can be conveniently and selectively reduced to alcohols with borane in tetrahydrofuran . Homoallylic alcohols have been dehydrated to the... 

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