Chm(cid:1005)(cid:1007)(cid:1006)(cid:1005) orga(cid:374)i(cid:272) che(cid:373)istry la(cid:271)oratory: preparatio(cid:374) of be(cid:374)zoi(cid:272) a(cid:272)id usi(cid:374)g a. Grignard reagents with the structure r-mg-x can be prepared by oxidizing mg metal with and organo-halide (r-x). The grignard reagents can be used to perform nucleophilic displacements of the pi bond of the carbonyl groups of aldehydes, ketones and esters (fairly active electrophiles) to form alcohol products. The reagents can also react with of one of the pi bonds on co2 to form a carboxoic acid that has one more carbon than the starting grignard reagent. The grignard regent phenyl magnesium bromide is prepared in the lab by reacting bromobenzene and mg metal in diethyl ether solvent. Anhydrous diethyl ether is aprotic, and thus a good choice for a solvent in this reaction, unlike water or alcohol, which would protonate and destroy the nucleophilic grignard reagent. Thus, the presences of any moisture would prevent the formation of the grignard reagent.