CHEMICAL REACTIONS

Question 1

Preparation of an Alkene can occur from?

Answer 1

An alcohol or alkyl halide

Question 2

What is the reagent for alkene preparation from an alcohol?

Answer 2

H2SO4 (a dehydrating agent)

Question 3

What is the reagent for alkene preparation from an alkyl halide?

Answer 3

KOH (or similar)

Question 4

The saytzeff rule applies to?

Answer 4

Alkene preparation from an alcohol or alkyl halide

Question 5

Hydrogenation of an alkene requires what reagent?

Answer 5

H2 (and palladium pd or platinum pt as a catalyst)

Question 6

Hydrogenation of an alkene occurs what what stereochemistry?

Answer 6

Syn stereochemistry (because pd or pt present H2 to only one side of the double bonded carbons)

Question 7

Addition of an electrophile to an alkene requires what reagent(s)?

Answer 7

HX or X2

Question 8

Addition of an electrophile to an alkene occurs with a?

Answer 8

carbocation intermediate

Question 9

markownikoff’s rule applies to?

Answer 9

addition reactions to alkenes (with asymmetrical reagents)

Question 10

electrophilic addition of X2 to alkenes results in what stereochemistry? why?

Answer 10

anti stereochemistry - brominium ion is formed in the intermediate

Question 11

electrophilic addition of X2 to alkenes involves?

Answer 11

an induced dipole in the X2 reactant

Question 12

the second halogen atom is electrophilic addition of X2 to an alkene is a…? why?

Answer 12

nucleophile, as it has a delta negative charge.

Question 13

hydrogenation of alkynes can involve what reagents?

Answer 13

Li/liq NH3 (heterosexual), lindlar catalyst (gay), platinum or palladium (goes to an ALKANE)

Question 14

hydration of alkynes involves what reagent?

Answer 14

H2O

Question 15

hydration of alkynes results in?

Answer 15

ketones or aldehydes

Question 16

what is the name of the equilibrium that is involved in hydration of alkynes?

Answer 16

tautomerisation equilibrium

Question 17

the tautomerisation equilibrium is between what products?

Answer 17

enol and aldehyde/ketone

Question 18

what is an alkynide ion?

Answer 18

a terminal alkyne in which an sp carbon has lost a hydrogen

Question 19

alkynide ions have a _ charge, thus are _-philes

Answer 19

negative, nucleophiles

Question 20

markownikoff’s rule also applies to alkynes. what is the reaction type and reagent in this case?

Answer 20

halogenation, HX

Question 21

there are two types of halogenation reactions of alkynes, what are the reagents of the two types?

Answer 21

HX or X2

Question 22

in halogenation of alkynes, what stereochemistry is observed? why?

Answer 22

anti (trans), halogen ion (similar to brominium)

Question 23

why can’t aromatic compounds undergo addition reactions?

Answer 23

because there is resonance energy (i.e., in the ring)

Question 24

what kind of reaction can aromatic compounds undergo?

Answer 24

substitution

Question 25

substitution reactions of aromatic compounds require a/an _-phile

Answer 25

electrophile

Question 26

the formal name of the resonance contributor in electrophilic aromatic substitution is?

Answer 26

wheland intermediate

Question 27

in wheland intermediates, the positive charge can only be in what positions? (relative to E)

Answer 27

ortho or para

Question 28

the process(es) for generating electrophiles for aromatic subsitution is/are called?

Answer 28

friedel-crafts acylation, friedel-crafts alkylation

Question 29

reagents in friedel-crafts acylation are?

Answer 29

haloaldehydes & AlX3

Question 30

reagents in friedel-crafts alkylation are?

Answer 30

haloalkanes & AlX3

Question 31

friedel-crafts acylation, and subsequent substitution onto an aromatic ring results in a _ product?

Answer 31

ketone

Question 32

friedel-crafts alkylation, and subsequent substitution onto an aromatic ring results in a _ product?

Answer 32

alkylbenzene

Question 33

what is a phenol?

Answer 33

an aromatic alcohol

Question 34

what is a nitrile?

Answer 34

CN

Question 35

what reagents are required to form an aromatic amine?

Answer 35

H2SO4 (dehydrant), HNO3 (nitric acid)

Question 36

ortho, para, meta classifications apply to what type of aromatic substitution?

Answer 36

disubstitution

Question 37

ortho, para, meta classifications apply to what type of reaction?

Answer 37

aromatic disubstitution

Question 38

ortho, para, meta are classifications relative to what?

Answer 38

the first aromatic substituent

Question 39

sn1 is favoured in what degree alkyl halides?

Answer 39

tertiary, some secondary, benzylic

Question 40

sn2 is favoured in what degree alkyl halides?

Answer 40

primary, some secondary

Question 41

the intermediate in sn1 mechanisms is called? what charge?

Answer 41

carbocation intermediate, positive