Question

Draw 1-bromo-2-iodoethane. Looking through the C-C bond, draw all 6 rotational conformations as Newman projections. Label the conformations as anti, gauche or eclipsed. Then, rank them in terms of lowest to highest energy. Explain your reasoning in 2-3 sentences.

Answer 1

Answer:

D > F = B > E = C > A

Explanation:

Newman projection is useful in studying the stereochemistry of the alkanes.

In the Newman projection, molecules are visualized from front to back. The front carbon is represented with dot whereas the back carbon with circle. different spacial arrangement of substituents around carbon are called conformers. Three conformers are staggered, eclipsed and Gauche.

Staggered is the most stable and Eclipsed is the most unstable. Staggered is also called anti

The 6 conformers of 1-bromo-2-iodoethane are shown in the attachment;

Order of the stability is as follows:

D > F = B > E = C > A

Anti is most stable because bulky group Br and I are opposite and hence stable.