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Why is para-toulenesulphonyl chloride used for reaction with Primary or secondary amine instead of Hinsberg reagent?
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+ Inorganic chemistry
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Michael Zorn
Why is para-toulenesulphonyl chloride used for reaction with Primary or secondary amine instead of Hinsberg reagent?
This is from Morrison and Boyd ORGANIC CHEMISTRY Second Edition 1966 : “ Alkyl sulfonates offer a real advantage over alkyl halides reactions where stereochemistry is important: this advantage lies, not in the reaction of alkyl sulfonates , but in their preparation . Whether we use an alkyl halide or sulfonate, and let it undergo substitution or elimination ,our starting point for the study is almost certainly the alcohol. The sulfonate must be prepared from the alcohol ; the halide nearly always will be .It is at the alcohol stage that any resolution wlll ,or any diastereomers separated ; the alcohol is then converted to a halide or sulfonate the reaction we are studying is carried out, and the products are examined.
Now, as is discussed in the following section, any preparation of a halide from an alcohol must involve the the breaking of the carbon-oxygen bond, and hence is accompanied by the likelihood of stereochemical inversion and the possibility of racemization. Preparation of a sulfonate ,on the other hand ,does not involve the breaking of the carbon - oxygen bond,and hence with complete proceeds with complete retention ; when we carry out a reaction with this sulfonate we know what exactly what we are starting with.
Most commonly used are estersopf p-toluenesulfonic acid : the p-toluene sulfonates. The name of the p-toluenesulfonyl group is often shortened to tosyl (Ts); p-toluenesulfonyl chloride becomes toysl chloride (TsCl) and p-toluene-sulfonates becomes tosylates (TsOR)
This is from Morrison and Boyd ORGANIC CHEMISTRY Second Edition 1966 : “ Alkyl sulfonates offer a real advantage over alkyl halides reactions where stereochemistry is important: this advantage lies, not in the reaction of alkyl sulfonates , but in their preparation . Whether we use an alkyl halide or sulfonate, and let it undergo substitution or elimination ,our starting point for the study is almost certainly the alcohol. The sulfonate must be prepared from the alcohol ; the halide nearly always will be .It is at the alcohol stage that any resolution wlll ,or any diastereomers separated ; the alcohol is then converted to a halide or sulfonate the reaction we are studying is carried out, and the products are examined.
Now, as is discussed in the following section, any preparation of a halide from an alcohol must involve the the breaking of the carbon-oxygen bond, and hence is accompanied by the likelihood of stereochemical inversion and the possibility of racemization. Preparation of a sulfonate ,on the other hand ,does not involve the breaking of the carbon - oxygen bond,and hence with complete proceeds with complete retention ; when we carry out a reaction with this sulfonate we know what exactly what we are starting with.
Most commonly used are estersopf p-toluenesulfonic acid : the p-toluene sulfonates. The name of the p-toluenesulfonyl group is often shortened to tosyl (Ts); p-toluenesulfonyl chloride becomes toysl chloride (TsCl) and p-toluene-sulfonates becomes tosylates (TsOR)
Hinsberg reagent is benzene sulphonyl chloride, which is not very different from para-toulenesulphonyl chloride. Both of them react in a similar manner, that is both form sulphonamide with primary and secondary amines. However, as far as I know, para-toulenesulphonyl chloride is more easily available reagent than benzene sulphonyl chloride. The other advantage is para-toulenesulphonyl amides form more easily and are more easily crystallisable. Therefore, they are more easy to identify than benzenesulphonyl amides.
Hinsberg reagent is benzene sulphonyl chloride, which is not very different from para-toulenesulphonyl chloride. Both of them react in a similar manner, that is both form sulphonamide with primary and secondary amines. However, as far as I know, para-toulenesulphonyl chloride is more easily available reagent than benzene sulphonyl chloride. The other advantage is para-toulenesulphonyl amides form more easily and are more easily crystallisable. Therefore, they are more easy to identify than benzenesulphonyl amides.
This is from Morrison and Boyd ORGANIC CHEMISTRY Second Edition 1966 : “ Alkyl sulfonates offer a real advantage over alkyl halides reactions where stereochemistry is important: this advantage lies, not in the reaction of alkyl sulfonates , but in their preparation . Whether we use an alkyl halide or sulfonate, and let it undergo substitution or elimination ,our starting point for the study is almost certainly the alcohol. The sulfonate must be prepared from the alcohol ; the halide nearly always will be .It is at the alcohol stage that any resolution wlll ,or any diastereomers separated ; the alcohol is then converted to a halide or sulfonate the reaction we are studying is carried out, and the products are examined.
Now, as is discussed in the following section, any preparation of a halide from an alcohol must involve the the breaking of the carbon-oxygen bond, and hence is accompanied by the likelihood of stereochemical inversion and the possibility of racemization. Preparation of a sulfonate ,on the other hand ,does not involve the breaking of the carbon - oxygen bond,and hence with complete proceeds with complete retention ; when we carry out a reaction with this sulfonate we know what exactly what we are starting with.
Most commonly used are estersopf p-toluenesulfonic acid : the p-toluene sulfonates. The name of the p-toluenesulfonyl group is often shortened to tosyl (Ts); p-toluenesulfonyl chloride becomes toysl chloride (TsCl) and p-toluene-sulfonates becomes tosylates (TsOR)
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This is from Morrison and Boyd ORGANIC CHEMISTRY Second Edition 1966 : “ Alkyl sulfonates offer a real advantage over alkyl halides reactions where stereochemistry is important: this advantage lies, not in the reaction of alkyl sulfonates , but in their preparation . Whether we use an alkyl halide or sulfonate, and let it undergo substitution or elimination ,our starting point for the study is almost certainly the alcohol. The sulfonate must be prepared from the alcohol ; the halide nearly always will be .It is at the alcohol stage that any resolution wlll ,or any diastereomers separated ; the alcohol is then converted to a halide or sulfonate the reaction we are studying is carried out, and the products are examined.
Now, as is discussed in the following section, any preparation of a halide from an alcohol must involve the the breaking of the carbon-oxygen bond, and hence is accompanied by the likelihood of stereochemical inversion and the possibility of racemization. Preparation of a sulfonate ,on the other hand ,does not involve the breaking of the carbon - oxygen bond,and hence with complete proceeds with complete retention ; when we carry out a reaction with this sulfonate we know what exactly what we are starting with.
Most commonly used are estersopf p-toluenesulfonic acid : the p-toluene sulfonates. The name of the p-toluenesulfonyl group is often shortened to tosyl (Ts); p-toluenesulfonyl chloride becomes toysl chloride (TsCl) and p-toluene-sulfonates becomes tosylates (TsOR)
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Hinsberg reagent is benzene sulphonyl chloride, which is not very different from para-toulenesulphonyl chloride. Both of them react in a similar manner, that is both form sulphonamide with primary and secondary amines. However, as far as I know, para-toulenesulphonyl chloride is more easily available reagent than benzene sulphonyl chloride. The other advantage is para-toulenesulphonyl amides form more easily and are more easily crystallisable. Therefore, they are more easy to identify than benzenesulphonyl amides.
Hinsberg reagent is benzene sulphonyl chloride, which is not very different from para-toulenesulphonyl chloride. Both of them react in a similar manner, that is both form sulphonamide with primary and secondary amines. However, as far as I know, para-toulenesulphonyl chloride is more easily available reagent than benzene sulphonyl chloride. The other advantage is para-toulenesulphonyl amides form more easily and are more easily crystallisable. Therefore, they are more easy to identify than benzenesulphonyl amides.
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