Learn about Organic Chemistry 7, in this comprehensive video by bannanaiscool.
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Rob Lederer: Cyclic or cyclic aliphatics are ones where you have those straight chains; well, they are not really straight chains now, you take the ends of the straight chains and pop off couple of hydrogens and you put them together in a circle. So, you don't really obey the general formula rules for their various groups, but they do have a circular type of nature to them. What would that be right there? Well, one, two, three carbons, all attached in a ring, well, that's a prop, but because it's in a circle, we call it cyclo; cyclopropane. Oh man! That's easy, That was kind of fun to do too, and it's going to be easier to draw than this. Nobody really does this kind of drawing here for the cyclical compounds when you can just do line diagrams for them, and you can do for this one a triangle. So that means -- what's that? That's a square, well, yeah but in organic chemistry, you can't write square down here and get marks for it. You got to look at that and say, 1, 2, 3, 4 carbons in a circle that's going to be cyclobutanol. Oh, yeah and that nice cyclobutanol. Now that one, that's a house. Yeah, as oppose to -- I could actually draw it better, so all of the sides are equivalent when I turn my head, but I'm not a very good artist. So, here is the deal. What's this one called? Oh, yeah now, you say, well, I get it, that's a cyclo there and five is pent, so it's going to be a cyclopentane, but what's on it? A branch; a methyl branch. So, it's going to be methyl cyclopentane. Chemguy, you forgot something. What did I forget? You forgot to put the one in front of the methyl, because the carbon is on the one. Well, anywhere you put it, in the circle, the carbon is always going to be the first carbon in the circle because that's going to be the most important carbon in the circle, the moment the branch on it. So, therefore that is just methyl cyclopropane, you don't have to say one. But sometimes you have to say, for instance, what would that be right there? Now this one is going to have two methyls on it; one is going to be at the one, the other one, keep going man, go clockwise because that's right, 1, 2, 3, 4, no, no, you don't do that, it's the lowest numbers possible; 1, 2, 3, yeah, this one would then be 1, 3-dimethyl cyclopentane. Halides are groups of certain elements. Halogens; fluorine, chlorine, bromine, iodine, astatine, although that one is not very popular for these type of reactions. Type of reactions; well, you can actually place those onto organic molecules by substitution or addition reactions generally and those are coming up later. So we need to be able to name them when we have substituted onto an organic molecule, a Halogen. So, what do we do here? Well, there is methane where hydrogen has been taken off and fluorine has been put on. All of the halogens, chlorine, bromine, iodine, fluorine, will become prefixes that will actually be the more important prefixes and the more complex ones if you name branches, we'll treat it like a branch really. Chloro, bromo, iodo and fluoro, so those are the prefixes that will utilize and we'll be naming this one now, well, it's a methane with a fluoro on it, so real simple, that's fluoro methane. Now, but if you have three Fs on there, that would be trifluoromethane. Now that would be a very important type of chemical that would act as a refrigerant really and that's like having a multiple fluorinated hydrocarbon. If you put chlorine on there to, now you got a chlorofluorocarbon and those are very damaging to the environment, because they will actually help to destroy the ozone layer, because those radicals will come off and create all kinds of mess for O3 up there in stratosphere. Now, let's look at this one, because this one is a little tricky one and teachers love to give this, and if they don't love to give it, they should be given, because it's a real important type of molecule and a real important type of thing that you would be able to know. What you're going to call