Draw the condensed structural formulas and give the IUPAC name...

Question

Draw the condensed structural formulas and give the IUPAC names for all the alcohols that have the formula C₅H₁₂O. (12.1)

Accepted Answer

Hi, everyone. Our next question says for the following condensed structural formula with corresponding Iupac nomenclatures, which of them satisfies the alcohol formula of C three H 80. And we have four different answer choices, each with two possible structures and sets of names. So we'll look through each of these thoroughly after we work our way through the possibilities. So we know that we have C three H 80 as our molecular formula. So we have three carbons and we know that we have an alcohol. So when we look at this structural formula or molecular formula, excuse me, we would subtract one hydrogen. So one H and 10 for the alcohol group and we're left with C three H seven. So we know that's what our alkyl group portion has to contain. So we would draw three carbons for our chain. And where can we put the alcohol group with a three carbon chain? That alcohol group can go on the terminal carbon, doesn't matter which one, the molecule will be the same, either way or the alternate placement would be, it could go on the middle carbon. So we've got these two possible structures that gives us our three carbons. We have our, oh, we have seven hydrogens left. Let's fill in the hydrogens and see if this structure meets that molecular formula. So in the first structure, our terminal carbon gets an H three, our middle carbon gets an H two. The carbon with the alcohol group also gets an H two. It has the alcohol group and a carbon attached to it. And the structure with the alcohol in the middle carbon, our terminal carbon gets an age three. Our middle carbon gets at just a single hydrogen because it has two carbons and an oxygen attached to it. Any other terminal carbon also gets an H three. Do these fit the formula? Our top structure, we have three plus two plus two plus one on the alcohol. So eight hydrogens and on the bottom structure, we have three plus one plus three and then one more on the alcohol. So again, eight hydrogens. So both of these structure possibilities bit are molecular formula of C three H 80. And when we look at the structures, they match choice a the first structure with the alcohol group on the end would be one propanol, it's propane because there are three carbons, the ol ending for the alcohol and the alcohol group is on carbon one in the second structure of the oxygen in the middle. The we still have a propanol three carbons but the alcohol group is on carbon too. So choice say one propranolol and two propol matches what we've figured out now to be thorough. Let's look at the structures in our other answer. Choices. Choice B the first structure is cyclopropane one all. But this is not a cyclopropane in the structure. This structure has a ring of four carbons with an alcohol group. So this would be cyclin one all. So cross B out. And indeed, if we look at structure two, we have sort of a cross shape a carbon in the middle with three methyl groups and an oxygen. But and it says T proin, but again, this has four carbons, it can't be a propranolol. It's a butanol. In addition, that's not Iupac naming when you have this TERT formulation. That is not an Iupac name but a common name. Choice C has the first molecule being butane three all. But again, it's not an alcohol. It's an ether because the oxygen is in a center with ethyl groups on either side. So that ending isn't even correct. And then of course, it has four carbons. So it can't be our molecule. The second structure is iso butanol which again, we don't have butane, we don't have four carbons. So choice C definitely incorrect. Joyce D has the first structure saying three butyl alcohol. But again, this is an ether, the oxygen is in the middle, it's attached to, it's attached the same way as two propanol in the middle of a propane chain. But then the oxygen on the other side has a methyl group, not a hydrogen. So it's an ether, not an alcohol. And the second molecule is ethane diol. So two carbons with an alcohol group attached to either side, but we only have one oxygen and we have three carbons. So that second structure definitely not possible. So choice d also incorrect. So once again, the possible structures that satisfy the alcohol formula of C three H 80 with their OPEC names are one propanol, that three carbon chain with the alcohol in the first carbon and two propanol, the three carbon chain with the alcohol in the second carbon. See you in the next video.

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Draw the condensed structural formulas and give the IUPAC names for all the alcohols that have the formula C₅H₁₂O. (12.1)

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