
According to Saytzeff’s rule the dehydration of 3,3 – dimethylbutan – 2 – ol gives a mixture of alkenes. But the secondary carbocation formed in this reaction undergoes rearrangement to form a more stable tertiary carbocation which further, undergoes to 13 – elimination leads more stable product, that is 2,3 – dimethyl but – 2 – ene (more yield). According to Saytzeff’s nile, 2, 3 – dimethyl pent- 2 – ene is the major product.