Thanks guys, any help will be great. It's an As Level past paper Chemistry question, I have answered it but I think I've gone wrong. I also have to explain how each type of isomerism arises?
2007-03-10 00:01:41 · 7 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
As mentioned, it can only be either an alkene or a cycloalkane, since you only have one unsaturation.
Structurally, you can have any of the following:
1-butene
2-butene
2-methylpropene
cyclobutane
methylcyclopropane
Of those, only 2-butene will have stereoisomers, cis (two CH3 groups on same side of molecule) and trans (opposite sides).
2007-03-10 00:53:53 · answer #1 · answered by TheOnlyBeldin 7 · 0⤊ 1⤋
Lets see -
C4H8 - automatically an alkene or cycloalkane
alkenes -
cis- and trans- configurations (also referred to as E and Z) are stereoisomers.
there is no chiral center hence no enantiomers
location of the double bond - diastereomers ( 1-butene, 2-butene)
methyl cyclopropane - location of methyl group with relation to the double bond (1-methyl cyclopropane, 2-methyl cylcopropane)
could also have a cylcopropane with a double bond in the side group however unlikely.
cyclobutane -all conformations are equivalent
Hope that starts you off
2007-03-10 00:14:54 · answer #2 · answered by Ravindra G 2 · 0⤊ 1⤋
1... But-1-ene ... CH2=CH-CH2-CH3 ... C4H8
2... But-2-ene ... CH3-CH=CH-CH3 ... C4H8
3... 2-Methylpropene ... CH2=C(CH3)-CH3 ... C4H8... (The methyl group forms a branch off the middle Carbon).
4... Methyl cyclo-propane ... 3 carbons in a ring with 1 attached to a methyl group. (Saturated). C4H8.
The following is not an isomer but is C4H8.
5...Cyclo-butane ...Carbons form a ring .. saturated...C4H8
2007-03-10 08:43:42 · answer #3 · answered by Norrie 7 · 0⤊ 0⤋
There are 4 isomers and two stereo isomers of each other
These include but-1-ene, but-2-ene (including the two stereo isomers cis-but-2-ene and trans-but-2-ene), 2-methyl-propene and cyclobutane (the only cycloalkane).
Hope that helps. There structures can be found in this website http://www.slc.ac.nz/WorkshopClub/Workshop/answersproblemsgeometricisomers.htm
2007-03-10 00:36:54 · answer #4 · answered by The exclamation mark 6 · 0⤊ 1⤋
Three types
But-1-ene and but-2-ene
but-1-ene does NOT have cis/trans isomerism.
but-2-ene does have cis/trans isomerism.
2007-03-10 08:39:11 · answer #5 · answered by lenpol7 7 · 0⤊ 0⤋
Six different isomers can be formed by the above formula
1.butene-1
2.cis-2 butene
3.trans-2-butene
4.2-methylpropene
5.cyclobutane
6.methylcyclopropane
2007-03-10 01:04:02 · answer #6 · answered by dushyant 1 · 1⤊ 0⤋
CH2=CH-CH2-CH3
CH3-CH=CH-CH3
CH3-C=CH2
|
CH3 (This one should be on the second C)
2007-03-10 00:17:41 · answer #7 · answered by tuoidabuon 2 · 0⤊ 0⤋