Organic 6: Addition Reactions of Alkenes

Question 1

Addition

Answer 1

reaction in which a reagent X-Y adds to a multiple bond so that X becomes attached to one of the carbons of the multiple bond and Y to the other

Question 2

Unsaturated hydrocarbons

Answer 2

alkenes commonly described as this because they have the capacity to react with substances that add to them

Question 3

Saturated hydrocarbons

Answer 3

alkanes commonly described as this because they are incapable of undergoing addition reactions

Question 4

Hydrogenation

Answer 4

addition of H2 to a multiple bond

Question 5

Heat of hydrogenation

Answer 5

heat evolved on hydrogenation of a substance; it is the value of -delta H (degree) for the addition of H2 to a multiple bond

Question 6

Heterogeneous reactions

Answer 6

reactions involving a substance in 1 phase with a different substance in a 2nd phase

Question 7

Syn addition

Answer 7

describes the stereochemistry of reactions such as hydrogenation in which 2 atoms or groups add to the same face of a double bond

Question 8

Anti addition

Answer 8

when atoms or groups add to opposite faces of the double bond

Question 9

Electrophilic addition

Answer 9

mechanism of addition in which the species that 1st reacts with the multiple bond is an electrophile (“Electron seeker”)

Question 10

Markovnikov’s Rule

Answer 10

when an unsymmetrically substituted alkene reacts with a hydrogen halide, the hydrogen adds to the carbon that has the greatest number of hydrogens, and the halogen adds to the carbon having fewer hydrogens

Question 11

Scientific method

Answer 11

defines science with 4 elements - observation, law, theory, and hypothesis

Question 12

Hydrolysis

Answer 12

a bond cleaved by reaction with water

Question 13

Hydration

Answer 13

addition of the elements of water (H, OH) to a multiple bond

Question 14

Microscopic Reversability

Answer 14

in any equilibrium, the sequence of intermediates and transition states encountered as reactants proceed to products in one direction, and in precisely the reverse order, in the opposite direction

Question 15

Le Chatelier’s Principle

Answer 15

a system at equilibrium adjusts so as to minimize any stress applied to it

Question 16

Spontaneous

Answer 16

a reaction that proceeds with a decrease in free energy (change in G is less than 0); the “official” definition: a process in which the entropy of the universe increases

Question 17

Free Energy (G)

Answer 17

the available energy of a system

Question 18

Exergonic

Answer 18

reactions for which the sign of delta G is negative

Question 19

Endergonic

Answer 19

reactions for which the sign of delta G is positive

Question 20

Hydroboration-oxidation

Answer 20

reaction sequence involving a separate hydroboration stage and oxidation stage; in the hydroboration stage, diborane adds to an alkene to give an alkylborane; in the oxidation stage, the alkylborane is oxidized with hydrogen peroxide to give an alcohol; the reaction anti-Markovnikov, syn hydration of an alkene

Question 21

Retention of configuration

Answer 21

stereochemical pathway observed when a new bond is made that has the same spatial orientation as the bond that was broken

Question 22

Vicinal

Answer 22

describing atoms or groups attached to adjacent atoms; in the case of a ____ dihalide, on adjacent Carbons

Question 23

Bromonium ion

Answer 23

a halonium ion in which the halogen is bromine

Question 24

Chloronium

Answer 24

a halonium ion in which the halogen is chlorine

Question 25

Halonium ions

Answer 25

a species that incorporates a positively charged halogen; bridged ___ ___ are intermediates in the addition of halogens to the double bond of an alkene

Question 26

Vicinal halohydrins

Answer 26

a compound containing a halogen and a hydroxyl group on adjacent carbons

Question 27

Peroxide effect

Answer 27

reversal of regioselectivity observed in the addition of hydrogen bromide to alkenes brought about by the presence of peroxides in the reaction mixture

Question 28

Epoxides

Answer 28

3-membered rings that contain oxygen

Question 29

Epoxidation

Answer 29

conversion of an alkene to an epoxide, usually by treatment with a peroxy acid

Question 30

Ozonide

Answer 30

a compound formed by the reaction of zone with an alkene

Question 31

Ozonolysis

Answer 31

ozone-induced cleavage of a carbon-carbon double or triple bond

Question 32

Dimer

Answer 32

molecule formed by the combination of 2 identical molecules

Question 33

Monomer

Answer 33

the simplest stable molecule from which a particular polymer may be prepared

Question 34

Polymer

Answer 34

a high-molecular weight material comprising a large number of monomer subunits

Question 35

Cationic polymerization

Answer 35

a polymerization in which the reactive intermediates are carbocations

Question 36

Polyethylene

Answer 36

a high-molecular weight polymer of ethylene

Question 37

Free-radical polymerization

Answer 37

an alkene polymerization proceeding via free-radical intermediates

Question 38

Coordination polymerization

Answer 38

a method of addition polymerization in which monomers are added to the growing chain on an active organometallic catalyst

Question 39

Polypropylene

Answer 39

a polymer of propene