Organomagnesium halides reactions with

The reaction of organolithiums or organomagnesium halide reagents with gold halides proceeds similarly to the copper halides in a 1 1 ratio. Their phosphine complexes can be isolated and characterized. In a 2 1 ratio, the transmetallation reaction is followed by ate complexation to form organoaurate complexes ... 

The reaction of organolithiums or organomagnesium halide reagents with silver halides produces organosilvers, but these are less stable than those containing Cu and Au and readily decompose to form homo-coupled products via alkyl radicals ... 

This method is less useful preparatively because in most cases the required organomercurials are obtained by the reaction of organomagnesium-halide reagents with mercury(II) halides ... 

Reactions of Enamine Salts with OrganometalUc Compounds Organolithium and organomagnesium compounds react with enamine salts to give amines substituted on the ix-carbon atoms. The treatment of. -dehydroquinolizidinium perchlorate (163) with alkylmagnesium halides gives 9-alkylated quinolizidines (164) (252,256). Formation of... 

The much simpler steroid, 253, was fortuitously found to fulfill this role when injected into animals. Its lack of oral activity was overcome by incorporation of the 7a-thioacetate group. Reaction of the ethisterone intermediate, 77b, with a large excess of an organomagnesium halide leads to the corresponding acetylide salt carbonation with CO2 affords the carboxyllic acid, 251. This is then hydrogenated and the hydroxy acid cy-clized to the spirolactone. Oppenauer oxidation followed by treatment with chloranil affords the 4,6-dehydro-3-ketone (254). Conjugate addition of thiolacetic acid completes the synthesis of spironolactone (255), an orally active aldosterone antagonist. ... 

The reduction of carbonyl compounds by reaction with hydride reagents (H -) and the Grignard addition by reaction with organomagnesium halides (R - +MgBr) are examples of nucleophilic carbonyl addition reactions. What analogous product do you think might result from reaction of cyanide ion with a ketone ... 

Allenyl and 1- and 2-alkynyl sulfoxides have also been prepared by reaction of organomagnesium halides with sulfinate ester 19. 1-Alkynyl p-tolyl sulfoxides were prepared in good yield from 1-alkynylmagnesium halides plus ester 19 in toluene (equation ll)63. The corresponding organolithium compound was unsatisfactory as a... 

The second route (Scheme 1) is a redistribution reaction, in fact the Schlenk equilibrium. This route may be used in the reverse direction for the preparation of pure diorganomagnesium compounds from organomagnesium halides. Addition of a ligand, usually dioxane, that forms an insoluble complex with magnesium dihalide, shifts the Schlenk equilibrium completely to the left side and allows isolation of pure diorganomagnesium compounds from the remaining solution. ... 

The dimeric organomagnesium halide complexes 187-189 (Figure 82) were obtained from the reaction of (2-Py)(SiMe3)2C-Sb=C(SiMe3)(2-Py) with Et2Mg in THF in the... 

There is one other report in the literature of a measurement of the enthalpy of formation of an organomagnesium halide. The enthalpy of reaction of magnesium with methyl iodide in ether was calorimetrically determined as —273.6 0.8 kJmoH Using a recent enthalpy of formation for liquid methyl iodide of —13.6 0.5 kJmoU, the enthalpy of formation of methylmagnesium iodide is —287.2 kJmoU. The exchange (equation 8) is thus 11.2 kJmoU endothermic. 

O-Benzyllactaldehyde dimethylhydrazone 230 allows a substrate control in the addition reaction of organomagnesium halides, leading almost exclusively to the 5yn-isomer 231 (equation 155) . The resulting hydrazide can be reduced on Raney Ni to the corresponding iyw-aminoalcohol 232. The stereoselective Grignard addition to a similar A-formyl hydrazone 233 proceeds with 92% diastereoselectivity (equation 156). The silylation of the amide nitrogen by TMSCl provides the pure iyw-adduct . 

The term Grignard reaction refers to both the preparation of a class of organomagnesium halide compounds and their subsequent reaction with a wide variety of organic and inorganic substrates. As such it has had a wide and profound influence on synthetic chemistry since its first elucidation by Victor Grignard at the beginning of the twentieth century. 

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