Ethylmagnesium bromide, and

Nitromethane reacts with t-BuNHMgBr (prepared from ethylmagnesium bromide and t-butylamine in boiling THF) to give the oxime 393 nitroethane yields the analogue 394. The action of PhN(MgBr)2 on 2-methyl-2-nitropropane (395) results in the azoxy compound 396432. 

N-Unsubstituted azomethine ylides may be generated thermally (79), and the N-metalated, 2-azaallyl anion versions may be generated by action of nonmetalhc bases such as l,8-diazabicyclo[5.4.0]undec-7-ene (DBU) on certain imines (80). Although they are assumed to show similar chemical properties, these two species usually show different reaction patterns, as shown in Scheme 11.7, where the regio-and stereoselectivities of the cycloadditions are quite different (24,78-80). Metala-tion of (alkylideneamino)acetonitriles can be performed with metallic bases other than LDA. Thus, butyllithium, ethylmagnesium bromide, and magnesium bromide-diisopropylamide are also effective (78). The N-magnesioazomethine... 

For instance, Trost, Mao and coworkers use a,a-disulfenylated lactones as enolate precursors . Reaction of ethylmagnesium bromide and a,a-di-(phenylthio)-)/-butyr-olactone provides such an enolate that is quenched by ethanal (equation 11). 

Dimethylpyrrolo[3,2- ]pyridine gives the 3-benzyl derivative with benzyl chloride in the presence of ethylmagnesium bromide and pyrrolof2,3-6]pyridine (4) reacts similarly with chloroacetonitrile in DMF at room temperature after pretreatment with sodium hydride (68AHC(9)27). All four pyrrolo[2,3]pyridines react with acrylonitrile in the absence of base to give mixtures of 2- and 3-alkylated derivatives (23 and 24 Scheme 7) (65BEP659467). 

Addition of Grignard reagents to acetylenic epoxides is exemplified by the reported condensations of ethylmagnesium bromide and of 1 -bromomagnesyl-5-methoxy-3 -methyl-3-pentea- L-yne with the epoxide depicted in Eqa. (839) and (840). In each case, products isolated... 

The sulfone is obtained by reaction of dimethyl sulfone with ethylmagnesium bromide and then with triflyl fluoride (CF3S02F, 3 M Co.), m.p. 115-116, yield 54%. 

Triethyl carbinol has been prepared by the action of zinc on a mixture of ethyl iodide and diethyl ketone 1 by the action of magnesium on ethyl bromide in diethyl ketone solution 2 as a by-product in the reaction between ethylmagnesium bromide and carbon oxysulfide 3 by the action of ethylmagnesium bromide on ethyl propionate 4 by the action of ethylmagnesium bromide on ethyl chloroformate 5 and by the action of ethyl-magnesium bromide on ethyl cyanoformate.6... 

The carbon skeleton can be assembled in one step by the reaction of ethylmagnesium bromide and ethyl acetate. 

Because the problem requires that ethanol be the ultimate starting material, we need to show the preparation of the ethylmagnesium bromide and ethyl acetate used in constructing the carbon skeleton. 

By treatment of the adduct with ethylmagnesium bromide and iron(m) chloride followed by acid. By acylation and ozonolysis. In the presence of lithium t-butoxide with diisopropylmagnesium alone, substantial amounts of reduction are observed. rfBy dehydration of the alcohol. "Reaction at -50° reaction in refluxing ether gave only 5%. Reaction in toluene containing 5% THF. 

For the synthesis of exo-brevicomin 617, the acrolein dimer was transformed mainly into the threo-DHP 614 by addition of ethylmagnesium bromide and chromatographic... 

The Mechanism of the cross coupling reaction can be accommodated by an oxidative addition of 1-bromopropene to iron(l) followed by exchange with ethylmagnesium bromide and reductive elimination. Scheme 3 is intended to form a basis for discussion and further study of the catalytic mechanism. In order to maintain the stereospecificity, the oxidative addition of bromo-propene in step a should occur with retention. Similar stereochemistry has been observed in oxidative additions of platinum(O) and nickel(O) complexes.(32)(33) The metathesis of the iron(lll) intermediate in step b is ixp icted to be rapid in analogy with other alkylations.(34) The formation of a new carbon-carbon bond by the redilcTive elimination of a pair of carbon-centered ligands in step c has been demonstrated to occur... 

The coupling of ethylmagnesium bromide and ethyl bromide to n-butane follows overall third-order kinetics, being first order in each component and the copper(l) catalyst. There is no evidence for alkyl radicals in the copper(I)-catalyzed coupling process, and we propose the following two-step mechanism ... 

E. Catalysis of Alkyl Disproportionation by Iron. Alkyl disproportionation is the sole reaction observed during the iron-catalyzed reaction of ethylmagnesium bromide and ethyl bromide.(47) The catalyst is a reduced iron species formed in situ by the reaction of iron(lI,III) with Grignard reagent, and ective... 

Acetylenic carbinols are prepared by the interaction of sodium acety-lides or acetylenic Grignard reagents with aldehydes. The formation and reaction of the metallic acetylide may be combined into a single operation. For example, an alkylacetylene in ether solution is treated successively with ethylmagnesium bromide and formaldehyde to give the acetylenic alcohol such as 2-heptyn-l-ol (82%). ... 

The rates of the reactions of equimolar quantities in 1 N diethyl ether solutions of ethylmagnesium bromide and 1-hexyne, at the reflux temperature of the mixture, were measured. Assigning the value of 100 to the rate of reaction of ethylmagnesium bromide (based on the half-life of the reaction) the relative rates of reaction of other organomagnesium compounds could be determined. The relative rates of reaction of methylmagnesium iodide and methylmagnesium bromide, for example, were both 6, and that of allylmagnesium bromide was 435. 

Preparation. Aniline is added dropwise with stirring to an ethereal solution of ethylmagnesium bromide and refluxing is continued for 30 min. 

Spirocyclopropanation of the dione 128 was noted on reaction with ethylmagnesium bromide and titanium tetraisopropoxide to give 130 in low yield plus the 1,2-addition product 129 <05TL8207>. 

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