Chem ch 13-2 Flashcards
saturated
saturated - alkane and cycloalkane. No double, triple bonds
unsaturated hydrocarbons
alkene (CnH2n) (alkene and cycloalkane are alaphatic), cycloaklene, and alkyne (CnH2n-2), aromatic - C6H6
= line structure for
ethene
CH2=CH2 condensed structure for
ethene
naming of alkenes (double bond)
- find longest chain but has to include the double-bond or triple-bond.
- number chain closer to double bond and indicate the number of the double bond.
- cycloalkenes do not require the numerical prefix
terminal alkene has
double bond at one end.
internal alkene has
bond in the middle
ethyne (kyna sour) the hydrogens are what?
H attached to triple bond are highly acidic.
diene - only used with what?
means 2 double bonds - REMEMBER - this will be the suffix in a cyclo for line or cyclo if there are 2 double bonds
types of stereoisomers
cis/trans alkanes
cis/trans alkene
REMEMBER - when naming, if it shows the geometrical structure…
add cis or trans.
more polar - cis or trans?
Cis
alkene and alkyne are polar or nonpolar?
NON POLAR. therefore, insoluble in water
can’t be cis or trans
alkyne
cylcoalkenes naming
same prefix - ending in O, suffix ends in ene - ex. 3-bromocylohexene
alkynes (3 bonds) are more___than alkene and alkane because…
unsaturated than alkene and alkane because they have less hydrogens (think-only 1 hydrogen)
have highly acidic hydrogens
alkynes
naming alkynes
same method but the main chain ends in yne.
if you have double bonds in a cyclo, you need to number them…
consecutively - ie - 1,2 NOT 1,6
c=c-c-c name it
1-butene (bond on the first carbon, and ene because it’s a double bond)
can’t tell if it’s cis or trans if it’s
molecular formula
cis and trans on line formation
Follow the angle of the bond, and you’ll know if it’s up or down.
if the lines attached to both sides of the bond are both facing down or up, it’s cis. if one goes up and the other down, it’s trans.
E/Z system
one w/ greater atomic mass has priority. To figure it out, draw a line down the middle of the bond, and compare the top and bottom groups. If the groups with higher atomic mass are on the same side, it’s cis.
E configuration
trans (opposite)
Z-configuration
together - cis
hydrogenation
adding H
halogenation
adding halogen group
hydration
adding H2O
hydrohalogenation
adding hydrohalide (H-OH) HCl
double oxygen bond connected to 2 other carbons (double azo)
ketone
alkanes - saturated or not?
saturated - only one bond
alkenes and alkynes - saturated or not?
unsaturated, they have more than one bond
aromatic - saturated or not?
unsaturated
functional group in alkene
the double bond
alkene formula
CnH2n
alkyne formula (same, but Kyna takes 2)
CnH2n-2
functional group in alkyne
triple bond
ethylenes
common name for alkene with 2 carbons - same as ethene
c=c
ethylene formula
3 carbon alkene called…
propene or propylene
c=c-c or c-c=c
propene
CH2=CHCH3
condensed formula for propene
c=c-c-c
butene
c-c=c-c and c=c-c-c are what?
double bond isomers - both butene. They are completely different compounds.
always number 1 and 2 where in cycloalkenes?
double bond in cycloalkenes, THEN number the side chain.
CH2=CHCH2CH3 name is…
1-butene BECAUSE the double bond is on the 1st carbon
H-C (triple bond) C-H name (2 names)
ethyne or acethylene
2n-2 is formula for
alkene and alkyne - this just means n = number of carbons. If you have 4 carbons, do 2(4) - 2 and that gives you the number of hydrogens.
when naming alkenes and alkynes..
remember that the bond always takes priority over the side chain when naming. If the bond is on carbon 2, then count from there to get to the side chain.
stop including prefixes..
in the cycloalkenes and alkynes
if you’re going backwards, and she gives you 4-methylcyclopentene and asks you to draw it, remember…
number 1 and 2 wherever you put the bond. it doesn’t matter where the bond is, just remember to number it 1 and 2, and then the side chain after that.
you can use cis or trans if the groups are..
both hydrogen and carbon, but if the groups are different (ie flourine or bromine) use E and Z.
don’t need to worry about cis or trans if it’s…
just a chain structure, ie. c-c-c
only do cis or trans if…
it’s a geometrical shape, either written out, like CH-C, or just the shape.
don’t need to worry about cis and trans for..
line structure
no cis or trans for..
alkyne
4 types of addition reactions
hydrogenation, halogenation, hydration, hydrohalogenation
in addition reaction with triple bond..
you need 2 moles of the reagent bc one mole only saturates one carbon bond, that leaves one more.
rearrangement
all of the same elements, just rearranged.
the product of rearrangement is..
isomers
