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Grignard reagents (RMgX) are prepared by the reaction of an organic halide and magnesium metal in ether solvent. R-X+Mgoverset(R-O_R)toR-MgX The solvent (usually diethyl ether or tetrahydrofuran) plays a crucial role in the formation of a Grignard reagent. Alkyl halides are more reactive than art and vinyt halides, Indeed, aryl and vinyl halides. Indeed aryl and vinyl chlorides do not form Grignard reagents in dethyf other. However, an att ha de containing an alcoholic - OH group can be converted to Grignard reagent by graf protecting the - OH group to a tert-butytdimethytslyt ether which is not to Grignard reagent. The protecting group is finally liberated by treatment with lotion R-O-H+Cl-underset("Tert-Butylchlorodimethyilance")underset(CH_(3))underset(|)overset(CH_(3))overset(|)(Si)-C(CH_(3))_(3)toR-O-Si-underset(CH_(3))underset(|)overset(CH_(3))overset(|)C(CH_(3))_(3)overset((C_(4)H_(9))N^(+)F^(-))toR-O-H+F-Si-underset(CH_(3))underset(|)overset(CH_(3))overset(|)C(CH_(3))_(3) Griganrd reactions generally occur in dry ether because |
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Answer» the stronger ACID diethly ether will DISPLACE the weaker RH acid from its salt |
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