Formation Of Vinyl Ethers

4 olefination of carbonyl substrates.

Formation of vinyl ethers.

In organic chemistry an enol ether is an alkene with an alkoxy substituent. Ethyl ether is an excellent solvent for extractions and for a wide variety of chemical reactions. 2 1 vinyl ether substrates. 2 2 allyl ether substrates.

It is also important that r is a good radical leaving group. The general structure is r 2 c cr or where r h alkyl or aryl a common subfamily of enol ethers are vinyl ethers with the formula roch ch 2 important enol ethers include the reagent 3 4 dihydropyran and the monomers methyl vinyl ether and ethyl vinyl ether. Silyl ethers are usually used as protecting groups for alcohols in organic synthesis since r 1 r 2 r 3 can be combinations of differing groups which can be varied in order to provide a. Glycol ethers decalin and 2 propanol are shown in group b of the previous section.

It is also used as a volatile starting fluid for diesel engines and gasoline engines in cold weather. Sakurai 177 has found that dicobalt octacarbonyl is an excellent catalyst for the reaction equation 67 and that the side reactions occurring through the use of the catalysts mentioned above e g. 3 2 alkoxide and silyloxide leaving groups. Molecular structure is the primary factor relating to a material s potential for hazardous peroxide formation.

These compounds produce organic peroxides that are significantly less volatile than the solvent in which they are. Silyl ether formation may be avoided. A stereospecific and stereoselective copper promoted coupling of vinyl pinacol boronate esters and alcohols allows the synthesis of enol ethers in very good yields is compatible with various functional groups and occurs at room temperature. These vinyl transfer reactions proceed in good yields with amide carbamate and sulfonamide nucleophiles and the optimal catalyst is dpp pd ococf3 2 dpp 4 7 diphenyl 1 10 phenanthroline.

The general structure is r 1 r 2 r 3 si o r 4 where r 4 is an alkyl group or an aryl group. Palladium ii complexes catalyze the formation of enamides via the formal cross coupling reaction between nitrogen nucleophiles and vinyl ethers. Methyl t butyl ether mtbe is a gasoline additive that boosts the octane number and reduces the amount of nitrogen oxide pollutants. Silyl enol ethers have been prepared by reaction of carbonyl compounds with hydrosilanes in the presence of palladium salts rhodium complexes and nickel salts.

3 1 halide and pseudohalide leaving groups. Dimethyl ether is used as a spray propellant and refrigerant. 2 3 acetylenic ether substrates. Silyl ethers are a group of chemical compounds which contain a silicon atom covalently bonded to an alkoxy group.

Cupric acetate is the copper source and triethylamine buffer is used to prevent protodeboration.