What is the difference between sec and tert

Odling in London, Edinb. Neo- even it is used today represents a terminal tert-butyl group, just like the prefix iso- represents a iso-propyl group at the end. According to my chemistry book O. Tandon's Organic chemistry ,if the prefix Iso is present in any compounds name then one methyl group is attached to second last carbon atom of the compound. Sec, Pri and Tert represents the carbon atom to which the functional group is attached to I. Cis and Trans can also be seen as prefixes, trans isomer has zero dipole moment since the atoms present are symmetrical.

The letter n can also be seen which means normal, the compound is straight. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. What is the logical way to understand Iso, Sec, Tert and Neo prefixes? Ask Question. Asked 2 years, 8 months ago. Active 2 years ago. Viewed 10k times. What seems logical to me is that an Alkyl molecule with the: " iso " prefix means its an isomer of that alkyl, the usual way i'd see it would be the alkyl group with a substituent the way an hexane could be isopentane if I got it right as for the " sec " prefix, the alkyl group is connected to the main molecule through a secondary carbon meaning the carbon on the alkyl is bonded with two other carbons in the alkyl, no consideration given to the main chain here I find the " tert " prefix similar to the latter, it is connected to the maine chain through a tertiary carbon bonded with three carbons on the alkyl I couldn't find a basic logical way to address the definition of the " neo " prefix.

Are the ways I described the rest of the prefixes correct? Improve this question. Let's draw the cyclopentane. So it'll just be a pentagon, so one, two, three, four, five, and it's a ring, so you can connect them. One, two, three, four, five.

Now, it doesn't matter where I draw the butyl group. It's all symmetric around there. We just have a ring and it's connected to a butyl group at some point. It'll start to matter once we add more than one group. So we can just pick any of these carbons to add the butyl group to. Now, just as a review, the but- prefix, that refers to, remember, methyl, ethyl, propyl, or meth-, eth-, prop-, but-. This is four carbons.

This is a four-carbon alkyl group. So let me just add it here. I could have added it to any of these carbons around this cyclopentane ring. So if I just add it right here, so I'm going to have four carbons. So one, two, three, four. That is the butyl part of this whole thing. And then let me just attach them up.

So you might be tempted to just draw this right there. And actually, this would be right. This is butylcyclopentane. But a question might arise. I just happened to connect the cyclopentane to the butyl at this first carbon on the butyl right there. I could have just as easily done it like this. I could have just as easily had it like this, where-- let me draw my butyl again, so I have one, two, three, four. So, once again, this is a butyl, but instead of being bonded to the cyclopentane on my first carbon, maybe it's bonded right here.

Let me do it with that yellow color. Maybe it's bonded right here. This seems like maybe this could also be butylcyclopentane. It looks like we have a butyl group. This is a butyl right here. I drew a butyl group right over here, and I also drew a butyl group right over here. But these are fundamentally two different molecular structures. I'm touching the first carbon here. I'm touching the second carbon over here. Now, there's two ways to differentiate this. One is the common naming and one is the systematic naming.

So let me differentiate between the two. So in the common naming, and this can get a little bit involved, and this frankly is probably the most complicated part of naming organic compounds.

Systematic is often more complicated, but it's easier to systematically come up with it. So there's a common and then there's a systematic. So the common way of doing it is, if you just say butylcyclopentane, that implies that you are bonding to the first or, depending on how you view it, the last carbon in the chain.

So this right here is butylcyclopentane. This right here is not just butylcyclopentane. What you would do is you definitely have a cyclopentane ring, so this would definitely be a cyclopentane. Let me put some space here. This is definitely going to be a cyclopentane. And you do have a butyl group on it, so we do have a butyl group, but because we are bonded-- we aren't bonded to the first carbon.

We're bonded to a carbon that is bonded to two other carbons. We call this sec-butylcyclopentane, so this is sec-. And everything I'm doing is obviously free-hand. If you were to see this in a book, the sec- would be italicized, or sometimes it would be written as s-butylcyclopentane. And this sec- means that we have attached to a carbon that is touching two other carbons. So you look at the butyl group, and say, well, which of these carbons is attached to two others?

It's either that one or that one. And regardless of whether you're attached to this or this, if you think about it, it's fundamentally the same molecular structure. So that's what you do when you're attached to that guy right over there. But what about the situation where we're dealing with just the common names right here?

What about the situation where it looks like this? So we have our cyclopentane right there, and we have a-- I guess we could call it a butyl group. It'll have four carbons in it, but let's say that the four carbons look something like this. Likewise for the isobutyl skeleton there is two ways to do it. Those are the only two ways to do it! This applies to other groups too. And if we used some other group, those four names — n -butyl, s -butyl, t -butyl or isobutyl — all remain the same.

Constitutional isomers. Iso butyl alc. But if it ha H10 then there is no space for -OH group. So the are positional isomers of eachother. Really helpful, thanks! I was trying to purely memorize which name went with which butyl, and I figured there had to be a logical explanation behind the name. You explained it really well. Very helpful. Read your explanation once. Got it. At the end where you go from Neopentane to Neopentyl Alcohol would the formula change to 2,2-dimethylpropanol because you added the OH?

Keep Up the Excellent Work! Its great to see individuals, such as yourself, helping students in need. This was so helpful! Can this apply to different carbon chains that are greater than butane? For example is it possible to have a tert-hexanol or isoheptane? Hi — no, it only applies to butane. In Wikipedia it is given as 1,1-dimethylethyl. I am confused. This section was really helpful.. But can you assure me that these terms sec,neo,tert,iso will not comes for others except butane.??

As in your section you were specific about butane..