Page 58 - Pharm.Org.Chem-I 02-06-05-101

(d) Rotate the molecule in such a way that
group 4 is pointing away from the viewer.

Here H has the lowest priority so it is in the back

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Arrow from group 1→2→3 is drawn.
If clockwise →(R)-isomer
If anti-clockwise → (S)-isomer.

(R)-2-Butanol

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