1. Isomers of C5H12O
by Dr.Gergens

2. Draw all fourteen isomers of C5H12O Goals:
draw all isomers & identify functional groups; alcohols (eight) & ethers (six)
identify methyl, primary, secondary & tertiary carbon centers
define a heteroatom and give examples
identify alcohol type as primary, secondary & tertiary alcohols
identify, name & draw branch names for
methyl
ethyl
n-propyl
isopropyl
n-butyl
sec-butyl
iso-butyl
t-butyl
• amyl
isoamyl
sec-amyl
• sec-isoamyl
• neopentyl
• tert-amyl
• give abbreviations for branch names
Me, Et, nPr, iPr, nBu, sec-Bu, iBu, t-Bu
give common and IUPAC to ethers and alcohols
identify chiral centers
identify planes of symmetry

3. The fourteen isomers of C5H12O - alcohols (eight)

4. The fourteen isomers of C5H12O - ethers (six)

5. The fourteen isomers of C5H12O - carbon centers
a CH3 bonded to a heteroatom is a methyl group
a heteroatom is an atom other than carbon C 1°
a carbon bonded to only one carbon is 1° primary C 2°
a carbon bound to two carbons is 2° secondary 3° C
a carbon bound to three carbons is 3° tertiary

6. The fourteen isomers of C5H12O - ethers (six) 1° primary carbons

7. The fourteen isomers of C5H12O - ethers (six) 2° secondary carbons

8. The fourteen isomers of C5H12O - ethers (six) 3° tertiary carbons

9. The fourteen isomers of C5H12O - alcohols (eight) 1° primary carbons

11. The fourteen isomers of C5H12O - alcohols (eight) 3° tertiary carbons

12. The fourteen isomers of C5H12O - alcohols (eight) 4° quaternary

13. The fourteen isomers of C5H12O - heteroatom centers
a CH3 methyl group bonded to a heteroatom is a methyl group
a heteroatom is an atom other than carbon
CH3 N O F Me C 1°
NH2 C 1° OH C 1° F
a heteroatom bonded to a 1° primary center is considered primary 2° C N H
a nitrogen heteroatom bonded to two carbons as a secondary amine 3° C N
a nitrogen heteroatom bonded to three carbons as a 3° tertiary amine

14. The fourteen isomers of C5H12O - heteroatom centers
a CH3 bonded to a heteroatom is a methyl group
a heteroatom is an atom other than carbon
CH3 N O F Me C 1° OH
a hydroxyl bonded to a primary carbon center is a 1° alcohol 2° C OH
a hydroxyl bonded to secondary carbon center is a 2° alcohol 3° C OH
a hydroxyl bonded to tertiary carbon center is a 3° alcohol

15. The fourteen isomers of C5H12O - 1°, 2° & 3° alcohols

16. The fourteen isomers of C5H12O - ethers (six) - branch names
methyl C
methyl C
methyl C
methyl C

17. The fourteen isomers of C5H12O - ethers (six) - branch names
ethyl C
ethyl

18. The fourteen isomers of C5H12O - ethers (six) - branch names
isopropyl C C 2° C C
n-propyl 1°

19. The fourteen isomers of C5H12O - ethers (six) - branch names
sec-butyl C 2°
n-butyl C 1°

20. The fourteen isomers of C5H12O - ethers (six) - branch names3° C
t-butyl
isobutyl 3° C C C C C C 1° C 3° 1° C C

21. The fourteen isomers of C5H12O - branch name abbreviations
t-butyl
tBu
isobutyl, iBu
methyl, Me
methyl, Me
ethyl, Et
sec-butyl
sec-Bu
isopropyl
iPr
methyl, Me
n-propyl, nPr
n-butyl
nBu
ethyl, Et
methyl,Me

22. The fourteen isomers of C5H12O - additional branch names
neopentyl C 3°
tert-amyl or
t-pentyl C 3° C 2°
sec-isoamyl
sec-isopentyl or
isoamyl C 1°
isopentyl or
sec-pentyl or sec-amyl
n-pentyl or n-amyl C C C 1° C C C C 2° C C C

23. The fourteen isomers of C5H12O - common naming of ethers
t-butyl methyl ether
isobutyl methyl ether
sec-butyl methyl ether
ethyl isopropyl ether
n-butyl methyl ether
ethyl n-propyl ether
KNOW these branch names used in these commonly named ethers.
Simple branch name are also used in naming alcohols and alkyl halides.

24. The fourteen isomers of C5H12O - IUPAC naming
2,2-dimethyl-1-propanol
1,1-dimethyl-1-propanol
3-methyl-2-butanol
2-methyl-1-butanol
3-methyl-1-butanol
3-pentanol
2-pentanol
1-pentanol
KNOW IUPAC traditional naming rules in naming alcohols, ALWAYS 1 & 2:
1) circle the longest continuous chain & 2) start numbering to the closest hydroxyl

25. The fourteen isomers of C5H12O - IUPAC naming
1,1-dimethyl-1-methoxyethane
2-methyl-1-methoxypropane
2-methoxybutane
2-ethoxy-2-propane
1-methoxybutane
1-ethoxypropane
KNOW IUPAC traditional naming rules, ALWAYS 1 & 2:
1) circle the longest continuous chain & 2) number to the closest branch

26. The fourteen isomers of C5H12O - chiral centers, asymmetric centers

27. The fourteen isomers of C5H12O - chiral centers, asymmetric centers

28. Identifying Chiral Centers
by Dr.Gergens

29. Not chiral-molecule has a plane of symmetery Not chiral-molecule has
Chiral-molecule is asymmeteric
Not chiral-molecule has
a plane of symmetery

30. Not chiral-molecule has a plane of symmetery Not chiral-molecule has
Chiral-molecule is asymmeteric
This carbon center is NOT chiral

31. Not chiral-molecule has a plane of symmetery
This carbon center is NOT chiral
This carbon center is NOT chiral

32. This carbon center is NOT chiral
This carbon center is chiral
This carbon center is chiral
This carbon center is chiral
This carbon center is chiral

33. This carbon center is NOT chiral
This carbon center is chiral
This carbon center is chiral

34. This carbon center is NOT chiral This carbon center is NOT chiral

35. This carbon center is chiral This carbon center is chiral

36. This carbon center is chiral This carbon center is chiral

37. These carbons center are NOT chiral This carbon center is NOT chiral
These carbons center are chiral
This carbon center is chiral
These carbons center are chiral
This carbon center is chiral

38. The fourteen isomers of C5H12O - alcohols (eight) - branch names
sec-pentyl or sec-amyl
n-pentyl or n-amyl C C C 1° C C C C 2° C C C

40. The fourteen isomers of C5H12O - alcohols (eight) - branch names2°
sec-isoamyl
sec-isopentyl or
isoamyl C 1°
isopentyl or

41. The fourteen isomers of C5H12O - alcohols (eight) - branch names
neopentyl C 3°
t-tert-amyl or
t-pentyl C 3°

42. The fourteen isomers of C5H12O - alcohols (eight) - branch names
neopentyl C 3°
t-tert-amyl or
t-pentyl C 3° C 2°
sec-isoamyl
sec-isopentyl or
isoamyl C 1°
isopentyl or
sec-pentyl or sec-amyl
n-pentyl or n-amyl C C C 1° C C C C 2° C C C

43. The fourteen isomers of C5H12O - ethers (six) - branch names
t-butyl
isobutyl
methyl
methyl
ethyl
sec-butyl
isopropyl
methyl
n-propyl
n-butyl
ethyl
methyl

44. The fourteen isomers of C5H12O - ethers (six)
t-butyl 1°
isobutyl 1°
methyl 3°
methyl 3°
ethyl
sec-butyl
isopropyl 1° 1° 2°
methyl 2° 2°
n-propyl
n-butyl
ethyl 1° 1° 2° 2° 2°
methyl

45. The fourteen isomers of C5H12O - alcohols (eight)
neopentyl 1°
t-tert-amyl
t-pentyl 1° 3° 4° 2° 1°
sec-isoamyl 1° 3° 2° 3° 2°
isopentyl 1° 2° 3° 1° 2° 2° 2°
sec-amyl
n-pentyl 1° 2° 2° 1° 2° 2° 2° 2°