Ethylmagnesium chloride

EtMgBr, Et20, it, 1 h, 90-100% yield. These conditions were used to prevent a neighboring silyl ether from migrating. Ethylmagnesium chloride is much more reactive thus, the reaction can be run at —42°, giving a 90% yield of the alcohol. Acetates and pivaloates are also cleaved. 

Grignard reagents (RMgX) Ethylmagnesium chloride, methylmagnesium bromide... 

The Grignard reagent 245 generated by treatment of optically active a-chlorosulfoxide 244 with ethylmagnesium chloride is hydroxylated by oxaziridine 33 to give secondary alcohol 246. The product was obtained in 80% yield and 91% ee <2000AGE3072>. 

The Raman spectra of diethyl ether solutions of ethylmagnesium chloride were very similar to that observed for the liquid. Furthermore, a change in the concentration of the... 

The concentration of Grignard reagent could also be a factor in the stereochemical outcome. The addition of ethylmagnesium chloride to 26 in diethyl ether was highly selective for the R R stereoisomer at concentrations of 0.09-0.72 M (81-83%). The chloromagnesium compound is associated even at low concentrations. The stereoselectivity of addition to 26 by ethylmagnesium bromide, which is monomeric at low concentration, is concentration-dependent. Selectivity for the R R isomer varied from 74% at 0.70 M, where the dipolar model 28 should dominate, to 55% at 0.044 M, at which the cyclic model 27 should be more important. The stereoselectivity for reaction of 26 with ethylmagnesium iodide is also concentration-dependent. 

Derivation By Grignard reaction of trichlorosilane and ethylmagnesium chloride. 

Ethylmagnesiation of homoallylic alcohols (ethers). Ethylmagnesium chloride can add to the double bond of homoallylic alcohols on catalysts with Cp2ZrCl2 with high stereoselectivity. In the case of the an/i-homoallylic alcohol 1 (R=H) the reaction proceeds with high an/i-selectivity in the case of both the alcohol and the methyl ether. In contrast to the reaction of the syn-homoallylic alcohol 3, the reaction proceeds with... 

The reaction of diazopentane with zirconium hydride at —40°C is reported (583) to jdeld dipentylzirconium, (C5Hn)2Zr, while the reaction of ethylmagnesium chloride, ethylsodium, or ethyllithium with zirconium tetrachloride (134) presumably results in the production of diethylzirconium dichloride. These products have not been completely characterized. 

The reaction of ethylmagnesium chloride and (77-Cp)2ZrCl2 at 0°C in methylene chloride results in a yellow crystalline product M hich presumably is C2H5Cp2ZrCl. It is a diamagnetic solid which is decomposed by light, air, or water, but is stable at 0°C under nitrogen (518). 

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