Reactions of Alkynes

Question 1

Syn-addition of H2 (cis-alkene formation)

Answer 1

H2 / Lindler’s Cat. or P-2 Cat.

Question 2

Syn-addition of H2 (alkane formation)

Answer 2

H2 / Pt

Question 3

Synthesis from geminal dihalides

Answer 3

1) 3 eq. NaNH2 / 2) H2O

Question 4

Anti-addition of X2 (alkene formation)

Answer 4

1 eq. X2 / CCl4 (X = Br, Cl)

Question 5

Markovnikov addition of HX (alkene + alkane formation)

Answer 5

1 eq. HX

Question 6

Ozonolysis

Answer 6

1) O3 / 2) H2O

Question 7

Anti-Markovnikov addition of HX (alkene formation)

Answer 7

1 eq. HX / ROOR (X = Br)

Question 8

Alkyne deprotonation

Answer 8

NaNH2

Question 9

Synthesis from vicinal dihalides

Answer 9

2 eq. NaNH2

Question 10

Hydroboration-oxidation (aldehyde formation)

Answer 10

1) (Benzene)2BH, THF / 2) H202, NaOH

Question 11

Alkylation

Answer 11

1) NaNH2 / 2) R’-X (R’ = Me or 1°)

Question 12

Anti-addition of X2 (alkane formation)

Answer 12

ex. X2 / CCl4 (X = Br, Cl)

Question 13

Hydration (ketone formation)

Answer 13

H3O+ / HgSO4

Question 14

Lindler’s Cat.

Answer 14

Pd, CaCO3, PdO2

Question 15

Markovnikov addition of HX (alkane only formation)

Answer 15

ex. HX

Question 16

P-2 Cat.

Answer 16

Ni2B

Question 17

Syn-addition of H2 (trans-alkene formation)

Answer 17

1) Na°NH3 (l) / 2) H2O

Question 18

H2 / Lindler’s Cat. or P-2 Cat.

Answer 18

Syn-addition of H2 (cis-alkene formation)

Question 19

H2 / Pt

Answer 19

Syn-addition of H2 (alkane formation)

Question 20

1) 3 eq. NaNH2 / 2) H2O

Answer 20

Synthesis from geminal dihalides

Question 21

1 eq. X2 / CCl4 (X = Br, Cl)

Answer 21

Anti-addition of X2 (alkene formation)

Question 22

1 eq. HX

Answer 22

Markovnikov addition of HX (alkene + alkane formation)

Question 23

1) O3 / 2) H2O

Answer 23

Ozonolysis

Question 24

1 eq. HBr / ROOR

Answer 24

Anti-Markovnikov addition of HBr (alkene formation)

Question 25

NaNH2

Answer 25

Alkyne deprotonation

Question 26

2 eq. NaNH2

Answer 26

Synthesis from vicinal dihalides

Question 27

1) (Benzene)2BH, THF / 2) H202, NaOH

Answer 27

Hydroboration-oxidation (aldehyde formation)

Question 28

1) NaNH2 / 2) R’-X (R’ = Me or 1°)

Answer 28

Alkylation

Question 29

ex. X2 / CCl4 (X = Br, Cl)

Answer 29

Anti-addition of X2 (alkane formation)

Question 30

H3O+ / HgSO4

Answer 30

Hydration (ketone formation)

Question 31

ex. HX

Answer 31

Markovnikov addition of HX (alkane only formation)

Question 32

1) Na°NH3 (l) / 2) H2O

Answer 32

Syn-addition of H2 (trans-alkene formation)