Naming Confussion!

life-is-once · Posted: Mon Mar 06, 2006 2:35 pm Post subject: Naming Confussion!

I Have A Problem In Naming Of Compounds !

If There Is A Compound Having The Branches On Same Carbon Atom Like 4-ethyl,3-Methyl Hexane.
From Whr We Start Numbering? From Methane Or Ethane
If From Methane Then Why Not From Ethane And If From Ethane Then Why Not From Methane?
If Some One GIve The Answer THANKX ALOT TO HIM/HER.

rsinh · Probably a bot. Joined: 10 Mar 2006 Posts: 1

in a compound where sum of locants(the carbons bearing substituents) is same then the carbon bearing a substituent which occurs forst alphabetically gets the lower number in chain

Macak · Junior Member Joined: 13 Jan 2006 Posts: 7

Substituents are listed in alphabetical order. To alphabetize, ignore numerical (di-, tri-, tetra-) prefixes (e.g., ethyl would come before dimethyl).

life-is-once

Sorry I AM Not Satisfied With These Answer I Think You Guys Did Not Got What I Wana Say!

My Question Is Simple
If A Methyl And Ethyl Branch Are On Same Carbon Atom Then Whom I Should Numbering?!

guanine · Posted: Mon Mar 20, 2006 1:48 am Post subject:

Dear life-is-once,

First off, 4-ethyl,3-Methyl Hexane doesn't have branches on the same carbon.

4-ethyl,3-Methyl Hexane looks like this:

(ignore the dots)

C-C-C-C-C-C
..... ..C..C
...... .....C

Secondly, you start naming on the longest chain (in this case, hexane) from the end closest to the first branch (in this case alphabetically):
6. 5. 4. 3. 2. 1
C-C-C-C-C-C
...... .C..C
....... ....C
So this would technically be 3-ethyl, 4-methyl hexane.

To answer your question about branches on the same carbon, let's look at 3-ethyl, 3-methyl hexane for example:

..... ..C
C-C-C-C-C-C
.. .....C
.... ...C
Again, number from the side closest to the first branch.

1. 2. 3. 4. 5. 6
.... ...C
C-C-C-C-C-C
.... ...C
.... ...C

So, in summary when numbering, number on the longest chain starting on the end closest to the first chain (alphabetically).

I hope this answers your question, and I hope that I didn't give you any missinformation but I'm pretty sure that this is the correct way of doing it.

guanine

P.S. If you understand this, try naming these and post the answers.

A)

..............C
C-C-C-C-C-C-C
..............C
..............C

B)
....C C
C-C-C-C-C
.......C
.......C

C) and for a tricky one

....C
C-C-C-C-C-C
...C
...C

life-is-once · Posted: Tue Mar 21, 2006 2:37 pm Post subject:

These Are Answers

A: 4-ethyl,4-methyl Heptane.

B:3-ethyl,2,3-di methyl Pentane.

C:3,3-di methyl Heptane.

I Hope I Give Right Name.
If Any Wrong Then Inform Me.

Jawad Ahmad Nizamani.

guanine · Posted: Tue Mar 21, 2006 7:21 pm Post subject:

Those are correct. Yeah. Very Happy

life-is-once · Posted: Wed Mar 22, 2006 10:29 am Post subject:

Thnkx

I Am Very Happy