1-Butylmagnesium bromide reaction using

The finely divided hydride produced by pyrolysis is pyrophoric in air, while synthesis from the elements produces a substantially air-stable product [1]. That prepared by reduction of butylmagnesium bromide with lithium tetrahydroalumi-nate is pyrophoric and reacts violently with water and other protic compounds [2], The hydride produced from magnesium anthracene has a very large specific surface area and is pyrophoric [3], In the context of use of the hydride for energy storage purposes, ignition and combustion behaviour of 100-400 g portions were studied, as well as the reaction with water [4],... 

To a stirred solution of 29 mg (0.2 mmol) of copper(I) bromide in 10 mL of diethyl ether under nitrogen are added 504 mg (4 mmol) of 3-[( R,R)- l,2-dimethyTl,2-ethanediylbis(oxy)]-l-propyne in 20 mL of diethyl ether. After cooling to — 50 °C lOmL (8 mmol) of a 0.8 M solution tert-butylmagnesium bromide in diethyl ether are added and the reaction is followed by TLC using cyclohexane. diethyl ether 90 10 as eluant. After completion, hydrolysis is achieved by the addition of 50 mL of aq NH3/NH4C1 and the product is extracted with diethyl ether. The solvent is evaporated and the pure product is stored over K2C03 yield 663 mg (90%) d.r. >98 <2. 

The addition of lithium bromide significantly increases the thermal stability of alkylsilver compounds.14 Westmijze and coworkers found that the reaction of n-butylmagnesium bromide, for example, with AgBr2LiBr gave a solution of butylsilver that was stable up to — 10°C, which is in stark contrast to the species obtained from the reaction with silver bromide alone, which decomposes at — 60°C. This marked stabilization of the alkylsilver compounds allowed for the first meaningful use of these reagents in intermolecular reactions. 

Similar to the conjugate addition, the focus of the last decade has been put on the development of chiral copper catalysts for enantioselective S -substitutions of prochiral substrates.197,197a,197b 271,285 These represent a useful alternative for the preparation of those substitution products which cannot be obtained by anti-stereoselective copper-promoted or -catalyzed SN2 -substitution of chiral substrates (see Section 9.12.2.1.2). The first reported example for such a transformation is the reaction of the allyl acetate 333 with //-butylmagnesium bromide in the presence of 15 mol.% of the copper arenethiolate 334 which gave the substitution product 335 with exclusive y-selectivity and 50% ee (Equation (18)),286 286a... 

Furthermore the CuCN catalyst is more regiospecific with the use of n-butylmagnesium bromide than with t-butylmagnesium bromide. The reaction with phenylmagnesium bromide also showed an excellent regioselectivity in favor of the 5 2 product. 

Lithiopyrimidines, -pyrazines, and -pyridazines have been converted by exchange with zinc chloride into the more stable zinc compounds " for use in palladium-catalysed couplings (section 11.5.2). Magnesium derivatives have been prepared by reaction of 5-bromopyrimidines with n-butylmagnesium bromide and cerium compounds (which give better results than lithiopyrimidines in reactions with enolisable ketones) can be prepared from either bromo- or lithiopyrimidine. ... 

Which reagent functions as the electrophile in the reaction of 1-butylmagnesium bromide and 2-methylpropanal, and why should it be freshly distilled before use ... 

---