October 17 - Nomenclature

Question 1

Straight chain alkanes

Answer 1

-ane ending
prefix to denote # carbons
add “cyclo” for cyclic alkanes

1: meth
2: eth
3: prop
4: but
5: pent
6: hex
7: hept
8: oct
9: non
10: dec

Question 2

Naming alkane fragments

Answer 2

Change “ane” to “yl” and add to beginning of word

Use same numerical prefixes

ex: methylcyclohexane
methyl is the alkane fragment

Question 3

Alkane fragment that looks trigonal planar

Special case

Answer 3

isopropyl-

Search up or look at notes to be reminded of this

Question 4

Alkane fragment that looks tetrahedral

Special case

Answer 4

tert-butyl-

Search up or look at notes to be reminded of this

Question 5

Naming branched alkanes

Answer 5

1. Find longest chain (not just from left-right or up-down, called the parent hydrocarbon), number it
2. Choose lowest numbers for alkane fragments
3. Arrange fragments in alphabetical order. Add prefixes if there are multiple of the same alkane fragments, number spot of each alkane fragment
4. When numbering in either direction leads to the same lowest number for one of the substituents, choose order of carbons that gives the lowest possible number to one of the remaining substituents
5. If the same alkane fragment #s are obtained in both directions, the lower # goes to the first group listed

Ignore prefixes for alphabetical order (pretend they aren’t there and sort normally)

If there are multiple of the same alkane fragment, number the place of each one

Question 6

Primary carbon

Answer 6

A carbon bonded to only one other carbon

Question 7

Secondary carbon

Answer 7

A carbon bonded to two other carbons

Question 8

Tertiary carbon

Answer 8

A carbon bonded to three other carbons

Question 9

Propyl group

Answer 9

3-carbon alkyl substituent with formula (-CH2CH2CH3)

Question 10

Isopropyl group

Answer 10

3-carbon alkyl substituent with formula (-CH2CH2CH3) connected to the hydrocarbon chain by the second carbon instead of the first

Question 11

Primary, secondary, and tertiary hydrogens

Answer 11

Are attached to primary, secondary, and tertiary carbons, respectively

Question 12

Parent hydrocarbon

Answer 12

The longest continuous carbon chain in a molecule

Question 13

Cycloalkanes

Answer 13

Alkanes with their carbons arranged in a ring

Add prefix “cyclo” to the alkane name

General formula: CnH2n

Question 14

Naming cycloalkanes

Answer 14

1. In a cycloalkane, the ring is the parent hydrocarbon
2. If the ring has two substituents, they are listed in alphabetical order and and #1 position is given to the substituent listed first

You don’t need to number the position of a single substituent (alkane fragment) on a ring

The first substituent listed in alphabetical order starts with a “1-“, then following ones are listed the same way branched alkanes (if a substituent is on the third carbon from the first substituent, it would be “3-“)