In the Newman projection for 2,2-dimethylbutane $\mathbf{X}$ and $\mathbf{Y}$ can respectively be

(B) H and $\mathrm{C}_{2} \mathrm{H}_{5}$; (D) $\mathrm{CH}_{3}$ and $\mathrm{CH}_{3}$

(C) $\mathrm{C}_{2} \mathrm{H}_{5}$ and H

JEE Advanced · 2010 · 11 Apr 2010 · Paper 1 · General Organic Chemistry

In the Newman projection for 2,2-dimethylbutane

X

and

Y

can respectively be

(A)H and H
(B)H and $C_{2} H_{5}$ ✓ Correct
(C) $C_{2} H_{5}$ and H
(D) $CH_{3}$ and $CH_{3}$ ✓ Correct

Answer: (B), (D)

Solution

2,2-Dimethylbutane has the structure (CH₃)₂CH–CH₂–CH₃. Looking at the Newman projection along the C2–C3 bond: the front carbon (C2) has two CH₃ groups and one H, while the back carbon (C3) has one C₂H₅ group and two H atoms. Depending on the rotation, X and Y can be: (B) H and C₂H₅, or (D) CH₃ and CH₃, representing different conformations of the molecule.

JEE Advanced · 2010 · 11 Apr 2010 · Paper 1 · One or more correct options

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JEE Advanced · 2010 · 11 Apr 2010 · Paper 1 · General Organic Chemistry

Solution

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