Alkene carboxylation

Applications of the cross-metathesis reaction in more diverse areas of organic chemistry are beginning to appear in the literature. For example, the use of alkene metathesis in solution-phase combinatorial synthesis was recently reported by Boger and co-workers [45]. They assembled a chemical library of 600 compounds 27 (including cisttrans isomers) in which the final reaction was the metathesis of a mixture of 24 oo-alkene carboxamides 26 (prepared from six ami-nodiacetamides, with differing amide groups, each functionalised with four to-alkene carboxylic acids) (Eq.27). 

Dubois and co-workers (119,410-415) characterized alkyl (R) substituent effects in simple and sterically congested alkanes, alkenes, carboxylic acid derivatives, ketones, amines, alcohols, and so on by the use of topological parameters XR ... 

C3 alkene Carboxylate ions, (epoxide) CH4, acetaldehyde, methanol, C02... 

A major factor dictating the product distribution of singlet oxygen ene reactions of a substituted alkene carboxylic acid salt (7) in water has been determined to be hydrogen bonding interactions between the solvent and substrate.6... 

SnCLrinduced cyclizations between alkenes and enol acetates result in cycloalkanes or bicycloalkanes in high yield (Eq. 59). It is interesting to note that the MesSiOTf-catalyzed reaction can yield fused rather than bicyelo products. Alkenic carboxylic esters, allylic alcohols, sulfones, and sulfonate esters are also cyclized in the presence of SnCU alkenic oxiranes, however, often cyclize in poor yield [89a]. 

Halo esters can be formed by addition of halogen atoms and ester groups to an alkene. Alkene carboxylic acids give a tandem reaction of formation of a halonium ion followed by intramolecular displacement of the carboxylic group to give a halo lactone. This tandem addition of X and OCOR is called... 

The hydroformylation of co-alkene carboxylic acid methyl esters catalysed by a Rh/TPPTS system (Scheme 1.22) in a biphasic medium does not require additives with low molecular substrates such as methyl 4-pentenoate, whereas methyl esters of higher co-alkene carboxylic acids such as methyl 13-tetra-decenoate require the presence of surfactants as mass-transfer promoters. Surfactants, indeed, decrease the interfacial tension, forming aggregates above the critical micellar concentration that speed up the catalytic process by increasing the interfacial area. 

SELENIC ANHYDRIDE (13768-86-0) OgSe Noncombustible solid. Violent reaction with water, forming selenic acid. A strong oxidizer. Violent reaction with many substances including reducing agents, hydrides, nitrides, and sulfides cyanides, esters, combustible materials, active metals, organic substances, aldehydes, alkenes, carboxylic acids, isocyanates, and thiocyanates. Attacks most metals in the presence of moisture. 

The Minisci reaction has successfully been applied for the alkylation of various heteroarenes, i. e. lepidine, pyrazine, quinoline and quinoxaline [2e, 2g, 10]. Organic compounds such as alkanes, alkenes, carboxylic acids, esters, amides, amines, alcohols, ethers, aldehydes, ketones, halides etc. have been successfully used as radical precursors in the Minisci reaction. A good overview of the different methods which have been applied to generate the alkyl radicals in these processes is summarized in [10b]. 

Allylic oxidation. Allylic alcohols are oxidized to enones by Pd(OAc)2 in wet DMF. Allylic esters are obtained from alkene/carboxylic acid mixtures on treat-... 

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