Chem Blk 2

Front 1

what are the 3 reaction to make a alkene?

Back 1

-catalytic dehydration

-acid catalysed dehydration

-base promoted dehydrohalogenation

Front 2

what is a catalytic dehydrogenation reaction for alkenes?

Back 2

it is when pt/heat is used as a reagent to strip an alkane of 2 H (in cis)

Front 3

what is acid catalysed dehydration to make an alkene?

Back 3

when concentrated H2SO4 is used to hip out a molecule of water from a ALCOHOL (trans)

Front 4

what is a base promoted dehydrohalogenation of alkyl halides? to make a alkene?

Back 4

when a reagent of (KOH in ETHANOL) to rip out a halogen (trans) and a H

Front 5

what is the saytzeff rule?

Back 5

the poor gets poorer (they have to be unsymmetrical product and reagent to get more than 1 product, unless its at the end)

the alkene that has the least hydrogens DIRECTLY attached to it is the major product. (always removes the H from the NEIGHBOURING carbon)

Front 6

looking at this molecule is unsymmetrical and the reactant is unsymmetrical so it will form 2 different products, determine what the products look like!

Back 6

the acid strips the OH and the H will be stripped on the carbon that is adjacent to the Oh-Carbon

so it will form these 2

Front 7

out of these 2 products which 1 is the major and minor and why?

Back 7

staff rule states the carbon in the alkene with the least hydrogens attached directly is the major product so we just have to count

Front 8

what are the types of reaction to do with alkenes? there are 3

Back 8

-hydrogenation

-halogenation

-addition of HZ

Front 9

what is a alkene hydrogenation reaction?

Back 9

when (H2 & Pt) to add 2 Hydrogens to an alkene to break the double bond to form an alkane. (CIS)

Front 10

what is a alkene halogenation reaction?

Back 10

when a halogen Br/Cl is added to a alkene and it breaks the double bond to form a TRANS haloalkane

Front 11

why does the alkene halogenation product en up trans?

Back 11

just remember how to draw this

Front 12

what is a HZ ?

Back 12

H is a hydrogen and Z is a (Halogen, OH, or OR group.)

Front 13

what is a addition of HZ reaction?

Back 13

when a HZ group is added to a alkene to break a bond and make new bonds with the reactants via a carbocation intermediate? to make trans

Front 14

what is a addition of HZ where it involves chloride, name the reactants and the product

Back 14

HCl(ignore the ether) is added to a alkene to break the double bond and a H is bonded to one carbon and a cl is bonded to the other in trans

Front 15

what reactant is used to turn an alkene into an ether, name reactant and configuration stereochemistry

Back 15

an H+ and a alcohol is added to the alkene. it forms an ether with a trans configuration

Front 16

what reactant is used to turn an alkene into a alcohol? name the reagent and the configuration?

Back 16

an H+ and H2O is added to an alkene to form an alcohol in the trans configuration

Front 17

what is markownikoffs rule?

Back 17

when there is an addition of an unsymmetrical reagent and reactant, to an unsymmetrical alkene.

The rich get richer

there will be more than 1 possible product, you look at the reactant the carbon on the double bond, which one has the most hydrogens, that carbon will gain 1 more H when it has the double bond broken. the functional group is put on the poor carbon

Front 18

draw the products of this and name the major and minor.

Back 18

the reactant and reagent is unsymmetrical so markownikoffs rule applies and 2 products is made

the richer carbon CH2 now become CH3, the rich got richer. and the poor carbon got the OH to make an alcohol

Front 19

there is a special reaction with alkenes that forms a dialcohol or diol. what reagent is used and what configuration is it?

Back 19

the reagent used is KMnO4 in AQ. NaOH

it gives a cis stereochemistry

Front 20

what is special about an ozonolysis reaction?

Back 20

it splits an alkene down the middle of the double bond and adding a O to both halves, double bond is still there and attached to the O. think of lysis is cleaving

Front 21

what reagent is used for ozonolysis?

Back 21

O3 and zn/H3O+

The zn/H3o is a catalyst and not used up

forms 2 ketones or aldehydes

Front 22

how do you make an alkyne?

Back 22

via didehydrohalogenation of a dihaloalkane

Front 23

what is a didehydrohalogenation of a dihaloalkane

Back 23

dehydrohalogention=removing H and a halogen

di means= 2

so a alkane with 2 H and 2Br gets removed to form an alkyne

with KOH or NaOH in ethanol (same as dehydrohalogenation of alkane--> alkene)

Front 24

how do you get a alkane from a simple alkyne?

Back 24

you use the reagent Pt + H2 to turn a alkyne to a alkene then to a alkane the reaction stops at alkane.

Front 25

how do you get a cis alkene from a simple alkyne?

Back 25

you react it with lindlar catalyst + H2

Front 26

how do you get a trans alkene from a simple alkyne

Back 26

you react it with Li/liq NH3 + H2O

Front 27

what is a addition reaction of water with an alkyne called?

Back 27

hydration reaction

by adding aq. h2s04/hgso4

usually forms ketones

Front 28

how is a hydration reaction done?

Back 28

Front 29

what a alkynide anion?

Back 29

where an alkyne at the end has a negative charge

RC-=C-

Front 30

whats a terminal alkyne?

Back 30

an alkyne with the triple bond at the end of the chain

RC-=CH

Front 31

how is the formation of alkynide anions from terminal alkynes done? name reactant reagents and all steps

Back 31

a terminal alkyne is reacted with a strong base (NA+NH2-) to remove a proton.

making the end C negative (an alkynide anion)

then you add in a HALOALKANE

the haloalkane adds itself to the chain at the C-

Front 32

what is resonance

Back 32

when the electrons in a pi bond move around usually around a benzene ring

Front 33

why is benzene more stable than other aromatics

Back 33

the increasing double bonds makes it more unstable for other aromatics because it requires more energy to hold it in place. however resonance makes benzene more stable less energy required to hold it in place

Front 34

does benzene rings undergo hydrogenation reactions?

Back 34

no only when it is a aromatic with only 1 double bond. or if the substituent of a benzene ring has a double bond. then the hydrogenation occurs on that double bond. with pt/h2 it breaks the bond and adds h2

Front 35

what is the equation used to calculate the amount of pi electrons in a aromatic structures?

Back 35

(4N+2)

N=number of aromatics

/2 to get number of double bonds

Front 36

what is a aniline?

Back 36

a benzene ring with a Nh2 group attached

Front 37

what is a benzoic acid?

Back 37

a benzene ring with a carboxylic acid attached

Front 38

what is a phenol?

Back 38

a benzene ring with a alcohol group attached

Front 39

what is a toluene?

Back 39

a benzene ring with a methyl Ch3 attached

Front 40

what is ortho?

Back 40

it is when on a benzene ring the 2 substituent groups are right next to each other on adjacent carbons

Front 41

what is meta?

Back 41

it is when on a benzene ring the 2 substituents on a benzene ring is 1 carbon apart (1 carbon in between the 2 )

Front 42

what is para?

Back 42

it is when on a benzene ring the 2 substituent groups are opposite each other.

Front 43

what reactions do benzene rings and substituted benzene rings usually undergo?

Back 43

substitution reactions

Front 44

what reagent is added to a benzene ring to add on a Bromine?

Back 44

Br2 + FeBr3 is substituted for a H on the benzene ring. giving us a benzene ring with a Br substituent.

Front 45

what is the mechanisms of a preparation of mono substituted benzenes such as adding br2+febr3 to a benzene to a get a bromobenzene?

Back 45

-an electrophile is added to a benzene

--wheland intermediate

-the E attaches the a carbon

-because it occupies the space of a double bond

it causes the other carbon to become a carbo

cation

-the neighbouring double bond then attacks it

resonance, so the electrons move and so does

the positive charge

-the + moves 2 carbons along

-it keep moving till it reaches ortho to the H+E

-the H attacks the carbocation, and this causes

the H to become H+ and detach as a proton

-what you are left with is a benzene with a E

-NOTE: the + is never Meta of the H+E

-NOTE the electrophile attack is very SLOW

-NOTE the proton loss is very FAST

Front 46

how are electrophiles usually generated?

Back 46

the electrophiles are usually formed by catalytic actions

such as

-halogenation

-nitration

-friedal crafts acylation and alkylation

Front 47

what is halogenation to produce a electrophile

Back 47

when a halogen group is split up and bonds with another molecule

X2+feX3

it is very reactive

the Fecl3 strips Cl from Cl2. giving a Cl+

the Cl+ is the electrophile that we want

and it can go ahead to bind to a benzene ring to give us the

Front 48

what is a nitration reaction to produce a electrophile?

Back 48

HNO3/H2so4 which will leave a NO2+ carbocation which will bind to a benzene ring giving a aniline

Front 49

what is friedal crafts acylation for creating a electrophile?

Back 49

my friend says its a ketone

a R-C^(=O)X /AlX3 is added to a benzene ring. the ALX3 strips the X leaving just a +R-C^(=O) carbocation

the ketone then gets attached to the benzene ring forming a kettle benzene thing

Front 50

what is friedal crafts alkylation for creating a electrophile?

Back 50

it uses RX/ Alx3(catalyst) (also alX3 strips the X in the process) to add the R+(carbocation)to a benzene ring.

benzene+RX/AlX3=

toluene

Front 51

how do you get a diazonium ion?

Back 51

so after you have a benzene+NO2 from a nitration reaction.

if you add a Fe/H+ it will become a aniline benzene + NH2

you then add Hno3 at O Degrees! to get a diazonium ion

which is

Front 52

what can you get from a diazonium ion?

Back 52

-carboxylic acids

-phenol

Front 53

how do you get a carboxylic acid from a diazonium ion?

Back 53

first of you need to get a benzene +cyanide

so you get that by adding CuCN to diazonium and you get a benzene+ CN

if you add H3O+ to Ben(CN) you get a benzoic acid

Front 54

how do get ben(C^(=O)Cl)

Back 54

if you add a reagent of SOCl2 to Carboxylic acid it will strip away the OH (alcohol) group on the carboxylic acid and replace it with a Cl.

Front 55

how do you get phenol form a diazonium ion?

Back 55

you add H3O+ this strips away the +N-=N and replaces it with a OH.

Front 56

what is a G group

Back 56

it is a molecule on a benzene ring what this molecule decides whether the electrophile that comes on is in ortho para or meta configuration

Front 57

what G groups cause the ortho-para and are STRONGLY ACTIVATING (makes the reaction faster)

Back 57

-OH

-OR

-NH2

-NR2

Front 58

what G groups cause the ortho-para and are weakly activating (makes reaction sorta faster)

Back 58

-CH3 (alkyl)

Front 59

what G groups cause the ortho-para but is DEACTIVATING? (making the reaction go slower to benzene)

Back 59

-X

(because they actually have quite a strong electronegativity so they pull the electrons back)

Front 60

what G groups cause the Meta and is Strongly Deactivating?

Back 60

=O

+N NO2

-O-

So3H

Front 61

what G groups cause the meta but is moderately deactivating

Back 61

-aldehyde

-carboxylic acid

-ester

-nitrile

Front 62

why is ortho para more stable than meta?

Back 62

because the ortho para has 4 resonance contributors

whilst the meta only has 3

Front 63

what are the names of the reaction to make an alkyl halide?

Back 63

-bromination

-chlorination

-addition of a HX to alkene

Front 64

what are free radicals?

Back 64

an atom with a unpaired valence shell electrons

Front 65

what are chlorination?

Back 65

it is when Hv light is used as a reagent and it is used to stick a X2 onto a usually alkyl chain

chlorination can form primary and secondary products

Front 66

what is bromination?

Back 66

when hv light is added to break a X2 and the free radical X is then attached to a H form a alkyl chain.

Front 67

what is bromination of toluene

Back 67

it is when toluene is reacted with reagents to add on a halogen group to the ring, however there are 2 different reaction you need to know.

one with Br2 HV+CCl4 or Br2/Febr3

Front 68

what happens when you react toluene with Br2 Hv + CCl4

Back 68

you get a toluene with a CH2Br attached to one another on the benzene ring

Front 69

what happens when you react toluene with Br2/FeBr3

Back 69

you get a toluene with a Br and a CH3 in the ortho-para direction as the CH3 is a orthopara director.

Front 70

what is an addition of HX or X2 to an alkene?

Back 70

when a HX is added to a Alkene through the bond breaking of the double bond and the H and X groups attach to it.

markownikoffs rules applies when unsymmetrical

Front 71

what happens when

CH3CH2CH=CH2 is reacted with HBr

Back 71

the H is attached to the richest C and the Br is attached to the poorest (that is only for the Major)

Front 72

what is a racemic mixture?

Back 72

when a carbocation is in a planar angle. it can have a nucleophile attack from the top or bottom causing a equal chance of getting a R or S configuration.

this is called a racemic mixture related to SN1 reactions

Front 73

how do you form a alkyne halide from an alcohol?

Back 73

when an halogen replaces a alcohol group on a R chain. there are 3 possible ways to do this

NOTE: X can only be CL or Br

Front 74

what do you react with ROH to get a alkyl halide? and SO2

Back 74

you add SOCl2 to ROH

the Cl replaces the OH

giving you RCl+So2

Front 75

what do you react with ROH to get Rbr

Back 75

you react PBr3 to ROH

the Br replaces the OH

and you get RBr

Front 76

what do you get when you react R3COH with HX?

Back 76

you get R3CX +H20

the X replaces the OH

Front 77

what are some reaction that can happen with alkyl halides?

Back 77

-substitution SN1 SN2

-elimination E1 E2

Front 78

what are the good leaving groups?

Back 78

mainly halogens

in order of least to most

Cl- , Br- , I-

(if on a carbon_

Front 79

what are the poor leaving groups

Back 79

H-, Bh2 , HO-, RO-

Front 80

what happens to a substitution reaction of

CH3C=-C- + CH3Br?

Back 80

the negative carbon attacks the CH3 binding it to become CH3C=-CCH3. the Br leaves because it is a good leaving group

Front 81

what is a SN1 reaction?

Back 81

unimolecular mechanism

occurs with alkyl halides

only SECONDARY AND tertiary

rate is determined by the conc of alkyl halides

SN1 is a substitution reaction

Front 82

what is the rate determining step?

Back 82

R.D.s the slowest part of the reaction usually determines the rate of the whole reaction

IN SN1 the formation of the carbocation is the slow step thats when the Br leaves and takes the electrons with it to leave a C+.

in SN2 because it all happens in one step the RDS is the whole reaction

in the end the O ends up positive, so the H is removed and it donates it electrons to O+ before it leaves so it becomes O and H+ leaves

Front 83

what is the reaction energy profile for SN1 reactions?

Back 83

the little dip pond thing is where the carbocation is formed. the first hump is when the X leaves, the second hump is when the other group is attached to

Front 84

what is a SN2 reaction?

Back 84

bimolecular (dependant of alkyl halide+Nu)

the rate is determined by alkyl halide+Nu

-Primary molecule and some secondary

-all done in 1 step

-no carbocation formed

-the product is always the reverse stereochemistry of the reactant. flipped umbrella

R<-->S

Front 85

what happens when you react a

Nu- + CH3Br?

Back 85

the Nu- will attack the Ch3 and the Br will leave

this all happens in a transition step (al at once)

[Nu...CH3....Br]--> Nu-CH3+Br-

Front 86

what is the energy profile graph for SN2 reaction

Back 86

the SN2 reaction occurs in a single step so it has only 1 hump

the weird symbol at the top and the hump is the transition state, where the everything happens at once occurs

Front 87

what is weird with the stereochemistry of SN2 reactions

Back 87

the stereochemistry is inverted form a R<-->S

Front 88

why does SN2 prefer primary

Back 88

because less carbons mean less crowded, because more crowding means more energy required in the transition state.