Vinylic halides hydrolysis

Cohen, T., Cristea, I. Copper(l)-lnduced reductive dehalogenatlon, hydrolysis, or coupling of some aryl and vinyl halides at room temperature. J. Org. Chem. 1975, 40, 3649-3651. 

Simple sulfonyl carbanions which do not contain additional carbanion-stabilising groups, e.g. carbonyl groups or heteroatoms, can be readily alkylated in high yield by modern techniques with the use of alkyllithiums and lithium amide bases. A number of allylic halides have been successfully used. In allylic halides, the halogen directly attached to the double-bonded carbon is relatively inert towards nucleophilic attack (Scheme 41). In this way, sulfones (96) can be transformed via desulfonation into vinyl halides (97) or into ketones (98) by hydrolysis (Scheme 41). In contrast to ordinary alkyl sulfones, triflones (99) can be alkylated under mildly basic conditions (potassium carbonate in boiling acetonitrile) (Scheme 42). The ease of carbanion formation from triflones (99) arises from the additional electron-withdrawing (-1) effect of the trifluoromethyl moiety. 

Grignard reaction, which see for Reagents available commercially. Apparatus. Analysis of RMgX. Gaseous halides. Entrainment procedure. Vinyl halides. Co-solvents. Inverse Grignard. Hydrolysis. 46 Examples. 

A large-scale synthesis of dialkyl 3-oxoaIkylphosphonates proceeds by treatment of dialkyl 1-copper(l)alkylphosphonates with 2,3-dihalopropenes. Low-temperature hydrolysis of the resulting vinyl halide with H2SO4 in biphasic medium releases the y-keto functionality (Scheme 7.56). Thus, alkylation of l-copper(I)alkylphosphonates with 1,2-dichloro- or l,2-dibromo-2-propene is equivalent to the introduction of masked 3- or 4-oxoalkyl groups. In this way, 1-substituted or unsubstituted 3-oxoalkylphosphonates are prepared in high yields (90%). ... 

There is no acid-catalyzed reaction for these compounds and halogenated aromatics (e.g., chlorobenzene) and vinyl halides are not susceptible to hydrolysis. This would account, in part, for the persistence of the PCBs and DDT related compounds. The rates of these reactions are influenced by bond strength, that is. 

A one-pot sequential and cascade sequence involving the formation of allylic azides, from aryl/heteroaryl/vinyl halides, allene and sodium azide, by palladium catalyzed anion capture, and cyclization-anion capture, followed by 1,3-dipolar cycloaddition provided a variety of 1,2,3-triazoles in good yields <01T7729>. Reaction of a,P-acetylenic aldehydes 107 with sodium azide in dimethylsulfoxide followed by hydrolysis afforded 5-substituted-4-carbaldehyde-1,2,3-triazole derivatives 108 <01TL9117>. 

Desuifonylation. Sulfones are useful in synthesis because alkylation a to the SOaR group is accomplished readily and the sulfone group can be eliminated after the alkylation by various reagents, particularly sodium amalgam (6%). Examples of the synthesis of vinylic halides by alkylation of sulfones with 1,3-dichloropropene and 2,3-dichloropropene are formulated, together with products of hydrolysis (aldehydes and ketones). ... 

The intermediate oxidation state of carbon in which there are two bonds to electronegative atoms is attained by reduction of acid derivatives or oxidation of alcohols and hydrocarbons. Interconversions at the same oxidation level such as hydration of alkynes and hydrolysis of vinyl halides are also valuable. 

A new type of catalyst, a cobalt carbonyl complex, has been found for low-temperature (viz. 50 °C) homogeneous hydroformylation of alkenes. Nafion-H (a superacidic perfluorinated resin sulphonic acid) impregnated with mercury is recommended as a catalyst for the hydration of alkynes R C=CR (R = H or aryl, R = H, alkyl, or aryl) to form ketones R CH2C0R. Two mild methods for the hydrolysis of vinyl halides to ketones have been described one utilizes Bp3,Et20 and mercury(ii) acetate in acetic acid and the second mercury(ii) acetate in trifluoroacetic acid/ ... 

Although poly(vinyl fluoride) resembles PVC in its low water absorption, resistance to hydrolysis, insolubility in common solvents at room temperature and a tendency to split off hydrogen halides at elevated temperatures, it has a much greater tendency to crystallise. This is because the fluorine atom (c.f. the chlorine atom) is sufficiently small to allow molecules to pack in the same way as polythene. 

Electrochemical reduction of oxazolinium salts 36 gives the anions 37, which add efficiently to alkyl halides or, in the presence of McsSiCl, to methyl acrylate, methyl vinyl ketone, and acrylonitrile. Simple acid hydrolysis then gives the ketone products 38 and 39, and this method is quite general since the starting salts are readily prepared from carboxylic acids, R C02H (87TL4411). 

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