A 1,2-rearrangement is an organic reaction where a substituent moves from one atom to another atom in a chemical compound. In a 1,2 shift the movement involves two adjacent atoms but moves over larger distances are possible. Examples are the Wagner-Meerwein rearrangement:

and the Beckmann rearrangement:

ओलीफिन मेटाथेसिस
1,2-पुनर्विन्यास
परिचय
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