Aitken

Question 1

Draw table for Hantzsch-Widman nomenclature system

Answer 1

Question 2

List the prefixes for the heteroatoms

(O, S, Se, Te, N, P, As, Sb, Si, Ge, B,)

Answer 2

O-Oxa - S - thia - Se - Seleno - Te - Tellura

N - Aza - P - Phospha - As - Arsa - Sb - Stiba

Si - Sila - Ge - Gerra

B - Bora

Question 3

How do you name a polycyclic System?

Answer 3

1. identify different rings present
2. Chose “Base Componant”
3. Consider where ring fuses.

Using the base ring, assign a letter for each side, then name the side where one ring joins to the other. If both rings are chiral / can create isomers depending on which part they join to, you must also figure the numbers for the atoms for the secondary ring.

Question 4

How do you decide the base ring of a base system?

Answer 4

1. is there one ring that contains nitrogen? if yes then that is the base.
2. is there no nitrogen in any of the rings? if yes, then chose the ring with a heteroatom that is “most important” i.e. O>S…
3. Is there more than two rings present? - if yes chose the component containing the most number of rings?
4. Are there two rings of different sizes? if yes, chose the larger one.
5. Do the rings contain different numbers of netero atoms? if yes chose the greater number.
6. Are there differences between the numbers of each kind of heteroatom in the two rings? if yes chose the ring with the greater number of ‘important’ heteroatoms. i.e. an n and an o is more important than the s and the n.
7. Chose the base component ring as the one where the heteroatoms have the lower numbers, i.e. 1,2 diaza, over 1,3 diaza

Question 5

Name this compound

Answer 5

thieno[3,2-b]pyridine

Question 6

Name this Compound

Answer 6

Benzo-b-Furan, note this is NOT benzo-c furan, which looks like =

Question 7

Name this Compound

Answer 7

1,2,4 - oxadiazole

Question 8

Where do you start number of a fused ring system?

Answer 8

One atom next to a ring junction

Question 9

What do you number ring junctions?

Answer 9

The number of the atom previous, along with the letter a, unless there’s two ring junctions in a row and the second will be nb, etc…

Question 10

How do you number multiple fused rings?

Answer 10

For multiple fused rings draw out the molecule out with the max number of rings horizontal, with any going off at an angle to the right, and begin the numbers on the most anticlockwise position on the top right ring.