CH3 - CH2 - CH - CH3
CH = CH2
The CH = CH2 is connected to the CH in the above line.
I think it is 3 methyl - 4 pentene. Am I right?
2006-12-02 07:53:10 · 6 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
I think it's funny how many people said it's a butene derivative. It's definitely going to be a pentene derivative since (as you've noticed) you can make a five carbon chain from the methyl group on the left to the methylene group after the double bond.
Your answer is close, but you can make the numbers lower. Double bonds beat methyl groups, so start with that. If you number it from the other end (so starting from the methylene on the bottom, next to the double bond), the double bond is on the first carbon, which is better than having it on the fourth carbon. Then, going back from there, the methyl group is still on the third carbon. So it's 3-methyl-1-pentene.
For this compound, you should still be able to come up with the right answer even if you don't remember that double bonds have priority over methyl groups, because when all the substituents have equal priority, you look for the direction that gives the lowest number at the first point of difference. In this case, the first point of difference is the first carbon. From one end it's just bonded to the next carbon in an alkane chain, whereas from the other end it's next to a double bond.
2006-12-02 08:38:56 · answer #1 · answered by Anonymous · 2⤊ 4⤋
I think it's 2-methyl-1-butene. The longest continuous chain which contains the double bond is four carbons long (the first three in the top row, plus the double-bonded carbon) so the base alkene is butene. The carbons are numbered from right to left as it's written here, because that puts the double bond in position 1, and numbering fron left to right would put it in position 3. That makes it 1-butene and puts the methyl group at position 2. Therefore the answer is 2-methyl-1-butene.
Edit: The way you wrote it is a little confusing. Did you mean that the CH in the line CH=CH3 was the same as the CH in the top row, or that it was bound to it? My answer is correct if they're the same. If they're bound, it's 3-methyl-1-pentene.
2006-12-02 08:03:27 · answer #2 · answered by Amy F 5 · 0⤊ 2⤋
Actually, if I believe the double bond gets priority in numbering, so it would be 3-methyl-pentene, also called 3-methyl-1-pentene. Leaving out the number for the double bond means it is in the first position.
2006-12-02 07:58:27 · answer #3 · answered by John S 2 · 1⤊ 1⤋
No, it's 2-methyl-1- butene. It's an alkene because of the double bond. because it is superior to the rest of the chain, it's named with the double bond as the first carbon and the methyl on the second carbon. Only a C with 4Hs is a methyl, and the longest chain has 4 members so it's butyl.
2006-12-02 08:04:43 · answer #4 · answered by boomer sooner 5 · 0⤊ 2⤋
Remember, when you name organic compounds with double or triple bonds, the numbering of the carbons should be that the double or triple bond carbon has the lowest number.
The answer should be 3-methyl-1-pentene
2006-12-02 08:01:18 · answer #5 · answered by Gabriel G 2 · 1⤊ 1⤋
I would call that "confusing"
2006-12-02 08:00:42 · answer #6 · answered by Anonymous · 0⤊ 2⤋