Carbon dioxide alkylation

Resonance Energies of Carbon Dioxide, Alkyl Isocyanates, etc. 

Esters Carboxylic acids Nitriles Ketones Amides Esters Nitriles Acyl chlorides Acid anhydrides Acyl cyanides Carbon dioxide Alkyl dialkoxyphosphinyl formate A l imidazoles Thiol esters Thio esters... 

Firstly, a group consisting of carbon monoxide, the cyanide ion and alkyl isocyanides, which exhibit chemical shifts in the range 12-37 p.p.m., and secondly a group made up of carbon dioxide, alkyl cyanides, isothiocyanates and the cyanate and thiocyanate ions with chemical shifts in the range 55-76 p.p.m. (from CS2). The groupings reflect similarities between the valence bond description of each set of compounds with their parent molecules, carbon monoxide and carbon dioxide. 

Acylating agents that have been employed are carbon dioxide, alkyl chloroformates, alkyl formates, add chlorides, esters, benzonitrile and dimethylformamide the expected acylation products from reaction with the above reagents were formed in each case. However, the N,N-dimethyl-amide derivatives of higher carboxylic acids did not yield acylated product as in the case of dimethylformamide . When R = H (equation 63), it was necessary to employ two equivalents of the lithiodithiane due to product enolate formation. 

An interesting feature of metal aUcoxides is the tendency to react stoichiometrically with some isoelectronic unsamrated molecules like carbon dioxide, alkyl or aryl isocyanates/ isothiocyanates, and carbodiimides (X=C=Y) to form metal derivatives as shown in Eq. (2.283) ... 

The 2-metalated thiazoles react with a variety of electrophilic substrates in a standard way, leading to addition products with aldehydes, ketones, carbon dioxide, epoxides, nitriles, Schiff bases, and to substitution products with alkyl iodides (12, 13, 437, 440). 

Hydrazine as Nucleophile. Reaction of hydrazine and carbon dioxide or carbon disulfide gives, respectively, hydrazinecarboxyhc acid [471-31-8], NH2NHCOOH, and hydrazinecarbodithioic acid [471-32-9], NH2NHCSSH, in the form of the hydrazinium salts. These compounds are useful starting materials for further synthesis. For example, if carbon disulfide reacts with hydrazine in basic medium with an alkyl haUde, an alkyl dithiocarbazate ester is obtained in a one-step reaction ... 

Peroxyesters undergo single- or multiple-bond scission to generate acyloxy and alkoxy radicals, or alkyl and alkoxy radicals and carbon dioxide ... 

Normally, alkyl peroxycarbamates undergo thermolysis to yield free radicals and carbon dioxide (20). 

The first-order decomposition rates of alkyl peroxycarbamates are strongly influenced by stmcture, eg, electron-donating substituents on nitrogen increase the rate of decomposition, and some substituents increase sensitivity to induced decomposition (20). Alkyl peroxycarbamates have been used to initiate vinyl monomer polymerizations and to cure mbbers (244). They Hberate iodine quantitatively from hydriodic acid solutions. Decomposition products include carbon dioxide, hydrazo and azo compounds, amines, imines, and O-alkyUiydroxylarnines. Many peroxycarbamates are stable at ca 20°C but decompose rapidly and sometimes violently above 80°C (20,44). 

Alkyl sulfonic acids are prepared by the oxidation of thiols (36,37). This reaction is not quite as simple as would initially appear, because the reaction does not readily go to completion. The use of strong oxidants can result in the complete oxidation of the thiol to carbon dioxide, water, and sulfur dioxide. 

Acryhc elastomers are normally stable and not reactive with water. The material must be preheated before ignition can occur, and fire conditions offer no hazard beyond that of ordinary combustible material (56). Above 300°C these elastomers may pyrolize to release ethyl acrylate and other alkyl acrylates. Otherwise, thermal decomposition or combustion may produce carbon monoxide, carbon dioxide, and hydrogen chloride, and/or other chloiinated compounds if chlorine containing monomers are present ia the polymer. 

Examples are given of common operations such as absorption of ammonia to make fertihzers and of carbon dioxide to make soda ash. Also of recoveiy of phosphine from offgases of phosphorous plants recoveiy of HE oxidation, halogenation, and hydrogenation of various organics hydration of olefins to alcohols oxo reaction for higher aldehydes and alcohols ozonolysis of oleic acid absorption of carbon monoxide to make sodium formate alkylation of acetic acid with isobutylene to make teti-h ty acetate, absorption of olefins to make various products HCl and HBr plus higher alcohols to make alkyl hahdes and so on. 

This reaction illustrates a stereoselective preparation of (Z)-vinylic cuprates, which are very useful synthetic intermediates. They react with a variety of electrophiles such as carbon dioxide, epoxides, aldehydes, allylic halides, alkyl halides, and acetylenic halides they undergo... 

Peresters are also sources of radicals. The acyloxy portion normally loses carbon dioxide, so peresters yield an alkyl (or aryl) and an alkoxy radical ... 

A chain mechanism is proposed for this reaction. The first step is oxidation of a carboxylate ion coordinated to Pb(IV), with formation of alkyl radical, carbon dioxide, and Pb(III). The alkyl radical then abstracts halogen from a Pb(IV) complex, generating a Pb(IIl) species that decomposes to Pb(II) and an alkyl radical. This alkyl radical can continue the chain process. The step involving abstraction of halide from a complex with a change in metal-ion oxidation state is a ligand-transfer type reaction. 

Perfluoroalkyl iodides can be directly carboxylated with zinc and carbon dioxide under ultrasonic conditions [39] (equation 45) or by the reaction of perfluoroalkyl iodides with carbon dioxide with a zinc-copper couple in DMSO [57] (equation 46) Alkylation of the intermediate carboxylate gives the corresponding ester [52]... 

Atid aie pioduced by passing carbon dioxide into tlie ether bolution of the magnesium alkyl compound. 

The reaction of tertiary alkylthioenyne alcohols (205) with carbon dioxide [70-73 atm, 70-75°C, Cu(I) salts, triethylamine] leads to 4,4-dimethyl-5-(alkyl-thioethenylmethylene)-l,3-dioxolan-2-ones (206) (79KGS1617 79ZOR1319). 

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