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What is the mechanism of the acid-catalyzed dehydration of 1-methoxy-2-methylcyclohexane to yield a mixture of alkenes? Draw the structures of the expected alkenes and explain which one is the major product and why.

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The acid-catalyzed dehydration of 1-methoxy-2-methylcyclohexane involves the following steps:1. Protonation of the methoxy group by a strong acid  e.g., H2SO4 or H3PO4  to form a good leaving group  methanol .2. Formation of a carbocation intermediate by the departure of the methanol group.3. Rearrangement of the carbocation  if necessary  to form a more stable carbocation.4. Elimination of a proton from a neighboring carbon to form a double bond  alkene .There are two possible alkenes that can be formed from the dehydration of 1-methoxy-2-methylcyclohexane:A  1-methylcyclohexeneB  3-methylcyclohexeneHere's the step-by-step mechanism:1. Protonation of the methoxy group by a strong acid to form a good leaving group  methanol .   O   ||CH3-O-CH CH3 C6H11  +  H+  -->  CH3-OH  +  CH CH3 C6H11+2. Formation of a carbocation intermediate by the departure of the methanol group.   CH CH3 C6H11+ 3. Rearrangement of the carbocation  if necessary  to form a more stable carbocation. In this case, no rearrangement is needed because the carbocation is already at the more substituted carbon  2 carbocation .4. Elimination of a proton from a neighboring carbon to form a double bond  alkene . There are two possible eliminations:A  Elimination from the carbon next to the methyl group:   CH2=C CH3 C6H11  1-methylcyclohexene B  Elimination from the carbon opposite to the methyl group:   CH2C CH3 =C6H11  3-methylcyclohexene The major product will be 1-methylcyclohexene because it is formed via the Zaitsev's rule, which states that the more substituted alkene is the major product in an elimination reaction. In this case, 1-methylcyclohexene has the double bond between two secondary carbons, while 3-methylcyclohexene has the double bond between a primary and a secondary carbon. Therefore, 1-methylcyclohexene is more substituted and will be the major product.

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