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Why don't we use an alkyl halide directly in Gabriel Phthalimide Synthesis?
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+ Biochemistry
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Marianne Komek
Why don't we use an alkyl halide directly in Gabriel Phthalimide Synthesis?
The goal is to make a primary alkylamine without causing polyalkylation. If you do not activate the pthalimide nitrogen with a base, you have a highly delocaled lone pair on the nitrogen. At best, you get an Sn1 reaction, however that will not give a primary amine as loss of the halide (if you can force it to go) will undergo Wagner-Meerwein rearrangement (hydride shift) to give a secondary or tertiary amine.
This is the point of the Gabriel phthalimide synthesis.
The goal is to make a primary alkylamine without causing polyalkylation. If you do not activate the pthalimide nitrogen with a base, you have a highly delocaled lone pair on the nitrogen. At best, you get an Sn1 reaction, however that will not give a primary amine as loss of the halide (if you can force it to go) will undergo Wagner-Meerwein rearrangement (hydride shift) to give a secondary or tertiary amine. This is the point of the Gabriel phthalimide synthesis.
It is used to make the conjugate base of the imide which is far more nucleophilic than the imide itself, but not too much to attack another molecule of the alkyl halide.
It is used to make the conjugate base of the imide which is far more nucleophilic than the imide itself, but not too much to attack another molecule of the alkyl halide.
The goal is to make a primary alkylamine without causing polyalkylation. If you do not activate the pthalimide nitrogen with a base, you have a highly delocaled lone pair on the nitrogen. At best, you get an Sn1 reaction, however that will not give a primary amine as loss of the halide (if you can force it to go) will undergo Wagner-Meerwein rearrangement (hydride shift) to give a secondary or tertiary amine. This is the point of the Gabriel phthalimide synthesis.
The goal is to make a primary alkylamine without causing polyalkylation. If you do not activate the pthalimide nitrogen with a base, you have a highly delocaled lone pair on the nitrogen. At best, you get an Sn1 reaction, however that will not give a primary amine as loss of the halide (if you can force it to go) will undergo Wagner-Meerwein rearrangement (hydride shift) to give a secondary or tertiary amine. This is the point of the Gabriel phthalimide synthesis.
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It is used to make the conjugate base of the imide which is far more nucleophilic than the imide itself, but not too much to attack another molecule of the alkyl halide.
It is used to make the conjugate base of the imide which is far more nucleophilic than the imide itself, but not too much to attack another molecule of the alkyl halide.
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