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| Mechanism of Racemisation |
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| A compound where the chiral carbon atom is attached to a hydrogen atom and an electron-attracting group can undergo racemisation readily. The mechanism is enolisation. For e.g., |
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| When the intermediate achiral enol form reverts to the stable form, there are equal chances to produce the dextro and laevo forms. Therefore ready racemisation is possible. |
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| Meso forms |
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| Meso forms are optically inactive because the rotation of the upper half is compensated by the rotation due to the lower half, which is in the opposite direction. Meso form of compounds cannot be resolved into active constituents. Therefore they are inactive, thanks to internal compensation. Meso forms of a compound have a plane of symmetry. |
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