Allyl magnesium bromide

Solid magnesium must be absent to avoid the formation of diallyl via allyl magnesium bromide the insertion of a short plug of glass wool effectively removes any finely divided magnesium. 

Grignard reaction, addition of allyl-magnesium bromide to acrolein, 41,49... 

A simple two-step protocol for the generation of a terminal diene is to add allyl magnesium bromide to an aldehyde or a ketone and subsequent acid or base catalysed dehydration (equation 34)72. Cheng and coworkers used this sequence for the synthesis of some indole natural products (equation 35)72a. Regiospecific dienones can be prepared by 1,2-addition of vinyllithium to a,/l-unsaturated carbonyl compounds and oxidative rearrangement of the resulting dienols with pyridinium dichromate (equation 36)73. 

Allyl bromide, in preparation of allyl-magnesium bromide, 41, 49 in preparation of allyltriphenyltin, 41, 31... 

A useful extension of the in situ anomerization process involves the employment of C-nucleophiles such as vinyl and allyl magnesium bromides. Grignard reactions to per-O-benzylated glycosyl iodides proceed stereoselectively when a strong nucleophile like allyl magnesium bromide is used, giving [1-C-allyl fucosides (95% P-only)... 

As an example of carbometallation, the 1,4-carbosilylation product 218 is obtained by the reaction of dienes, disilanes and acid chlorides of aromatic and a,/i-unsaturatcd acids at 80 °C. The phenylpalladium 216 is formed by the oxidative addition of benzoyl chloride, followed by facile decarbonylation at 80 °C, and reacts with butadiene to generate the benzyl-7i-allylic complex 217. Then, transmetallation with the disilane and reductive elimination afford 4-silyl-2-butenylbenzene 218 [92], Regioselective carbomagnesation of isoprene with allylic magnesium bromide 219 catalysed by Cp2TiCl2 gives 220, which is useful for terpene synthesis [93,94],... 

Allyl magnesium bromide Thionyl chloride Hydrochloric acid... 

Results. As the data in the literature show, the NMR spectrum of allyl magnesium bromide in ether solution (15) can be interpreted most easily by assuming that a rapid exchange of two isomeric forms occurs. The rate of this exchange is very high, and at — 80°C. it is more than 1000 times per second. 

Becker, C. C., Rosenquist, A., and Holmer, G. 1993. Regiospecific analysis of triacylg-lycerols using allyl magnesium bromide. Lipids, 28,147-149. 

Bercaw and co-workers showed that pentamethylcyclopentadienyl-aminoborole complexes of hafnium and zirconium 52 react with allyl magnesium bromide in diethyl ether to yield the allyl complexes 53 (Equation 8) <1997JOM65>. 

Allylboronate 196 is prepared from the reaction of allyl magnesium bromide with trimethylborate followed by esterification with diisopropyl tartrate (DIPT) in the presence of MgS04 (Eq. (11.13)) [116]. In analogous fashion, the (E)- and (Z)-crotylboronates 219 and 213 are prepared [139] in high isomeric purity (>98%) from ( )- and (Z)-2-butene by way of the (E)- and (Z)-crotylpotassium... 

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