Conversions Between Molecule View and Chair View

Key Questions

  • This, for example, can apply to ortho (1,2 connections) compounds. If carbons 1 and 2 have non-hydrogen substituents, trans implies that one substituent is in the back and one is in the front. If both are in front or both are in back, it is cis. Note that it also extrapolates to meta (1,3) and para (1,4) connections.

  • Answer:

    Trans alkenes are more stable than cis alkenes because they have fewer steric interactions.

    Explanation:

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    In cis-but-2-ene, there is steric hindrance, because the methyl groups are on the same side of the double bond.

    Because of this steric crowding, there are van der Waals repulsive forces between the electron clouds of the groups.

    This decreases the stability of the cis alkene.

    In trans-but-2-ene, the methyl groups are on opposite sides of the double bond, and the repulsion does not occur.

  • This, for example, can apply to ortho (1,2 connections) compounds. If carbons 1 and 2 have non-hydrogen substituents, trans implies that one substituent is in the back and one is in the front. If both are in front or both are in back, it is cis. Note that it also extrapolates to meta (1,3) and para (1,4) connections.

Questions