Select the newman projection that corresponds to the following molecule

Select the Newman projection that corresponds to t
Please help with this question

Answer

General guidance

Concepts and reason
Chirality center: An atom (usually carbon) which is bonded to four different atoms or groups is known as chiral center. In the chair conformer, if the atoms are facing towards up, then those atoms must be placed at above the plane in cyclohexane ring structure. Similarly, if the atoms are facing towards down, then those atoms must be placed at below the plane in the cyclohexane ring structure. Conformation is formed due to free rotation around carbon-carbon single bond. Conformations can be represented by Newman projection or sawhorse projection. In Newman projection, there are basically two forms that is, staggered and eclipsed which represents the various conformation of a molecule. While drawing the Newman projection from the wedge-dash representation, the groups which are in above the plane should be placed in the right side in Newman projection, similarly the groups which are in below the plane should be placed in the left side of Newman projection. The Newman projection of cyclohexane is as follows: 工一
H-2H
fó
十H
-
政
H
5
UIT

Fundamentals

Cyclohexane is more stable in its chair conformation. In chair conformation of cyclohexane, two types of groups are present at each carbon atom. They are axial and equatorial groups. The six axial bonds one on each carbon, are parallel and alternate up-down. The six equatorial bonds one on each carbon, come in three sets of two parallel ring bonds. Equatorial bonds alternate between sides around the ring. In Newman projection, the circle represents the back carbon. The front carbon is represented with three lines meeting at the center of the circle. The Newman projection is represented as,

Step-by-step

Step 1 of 2

The chair conformation is as follows: CH,
CH3
-
м
нес-
Сн,
н
5
ОН
ОН

The –OH and the methyl groups are represented towards down in the chair form at 1st and 2nd positions. Another methyl group is represented towards up in the chair form.

Step 2 of 2

The Newman projection is as follows: CH3
H
TH
H
山。
H₃C/
| Hact
H、
圳
fom DOT
<
/
_H
H
5}
ОН
HO

The Newman projection for the provided structure is as follows: C
ОН


In the chair conformation, the –OH group is in axial position, methyl substituent at 2nd carbon is in equatorial position and another methyl group at 4th carbon atom is in axial position. The chair form is represented in Newman projection. In the Newman projection, the –OH and the methyl groups (at 1st and 2nd carbon atoms) are gauche to each other. Similarly, the two methyl groups (at 2nd and 4th carbon atoms) are anti to each other.

Answer

The Newman projection for the provided structure is as follows: C
ОН

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