Question

What is the structure of 2-methyl-butan-1-ol as displayed formula?

First structure that came up for 2-methyl-butan-1-ol online:

-------------H-----
--------------I-----
---------H - C - H
-----H--H---I---H
-----I----I----I----I
H - C - C - C - C - O - H
-----I-----I----I----I
----H----H---H---H

Second structure that came up for 2-methyl-butan-1-ol online:

---------H--------
----------I----------
----H - C - H----
----------I-----
---- H - C - H
-----H---I---H
-----I----I----I
H - C - C - C - O - H
-----I-----I----I
----H----H---H

These two different structures kept coming up in different websites. I do not know which one is right. How can 2-methyl-butan-1-ol have two different structures come up for it? I am confused. Which structure is right?

Answer 1

Those two structures are the same.
On the first one the four C atoms left to right are the butane back bone. On the lower one the C-OH is the first C, the next C on the left from the C-OH is carbon 2 and the next C is the CH3 methyl group. On Carbon 2 go UP and you will see carbon 3 and carbon 4 to make the butane back bone. Remember that the carbon chain need not be in a straight line. The lower one is more easily seen if we draw it with fewer lines.I have placed a * for the C atoms that make the butane back bone. You can see that the methyl is on carbon 2 which is the second C from the OH group C.
-------C*H3
--------|
-------C*H2
--------I
CH3-C*H2-C*H2OH

Answer 2

1) Should the first structure or second structure of 2-methyl-butan-1-ol be drawn if asked?

2) Would the displayed formula with fewer lines not have CH and not CH2 for the second carbon?

-------C*H3
--------|
-------C*H2
--------I
CH3-C*H-C*H2OH

3) Is * used everywhere to show the backbone in a displayed formula? Should I use it?