D. V. Bazhenov

Trans-acetoxymercuration of diphenylacetylene

Abstract In contrast with literature data, the acetoxymercuration of diphenylacetylene proceeds to give trans -adduct, 2, the configuration of which was established on the basis of 13 C, 199Hg NMR and X-ray data.

Regioselectivity in the reaction of polyfluorinated β-diketones with hydroxyl-containing nucleophiles

ConclusionAddition of water to nonsymmetrical β-diketones containing one fluoroalkyl substituent takes place at the grouping of the enol form. Increasing the length of the fluoroalkyl substituent from HCF2 to n-C4H9 results in a reduction in the amount of the hydrated form.

The reaction of mercuric salts with dimethyl bicyclo[2.2.2]octa-2,5-diene-5,6-dicarboxylate

The regioselectivity and stereochemistry of the reaction of mercuric salts with dimethyl bicyclo[2.2.2.]octa-2,5-diene-5,6-dicarboxylate were studied in different solvents. The factors determining the reaction regioselectivity were considered.

Reaction of α-halogen-substituted fluorine-containing β-keto acids with ho- and hs-nucleophiles

Conclusions1.Using1H and19F NMR spectroscopy, it was shown that for methyl esters of fluoroalkyl-containing a-chloro-substituted β-keto acids, the keto form is most reactive in reactions with HO-nucleophiles (water, methanol) and HS-nucleophiles (ethyl mercaptan), in contrast to the β-keto esters which do not contain α-halogens.2.Methyl esters of fluoroalkyl-containing α,α-dibromo-substituted β-keto acids form adducts at the keto group with methanol and ethyl mercaptan, and with acetone give β-keto esters unsubstituted by bromine at the a position and bromoacetone. The latter reaction is accelerated by both acid and basic catalysts.

Reaction of fluorinated β-dicarbonyl compounds with ethylmercaptan

ConclusionsAddition of ethylmercaptan to fluorinatedβ-diketones proceeds through the enol form at the carbon atom bound to the fluoroalkyl substituent; with fluorinatedβ-ketoesters it is also the enol form which reacts with the mercaptan.