1

Question 1

alkyne carbon is __ hybridized resulting in

Answer 1

SP
50%s 50% p increase in s character, closer to nuc.
linear

Question 2

alkyne naming

Answer 2

logest chain with alkyne
substuents (prefix not matter, alfabetical)
alkyne has smallest #

(ending yne)

Question 3

alkyne vs doubled and single bonded CB

Answer 3

closer to nuc, more stable (A stronger because CB more stable = weaker CB)

Question 4

acid strength for alkyne deprotination

Answer 4

must be stronger (NaOH not work, NaNH2 work)

Question 5

equlibrium favorst the

Answer 5

weaker side

Question 6

geminal alkyne

Answer 6

same C attom

Question 7

vinical alkyne

Answer 7

adjacent C attoms

Question 8

Synthesising alkynes

Answer 8

Need strong base via an E2 rxn

1) xs NaNH2
2) H2O

Question 9

synthsizing alkynes via a strong base is better with ____ instead of ___ because __

Answer 9

terminal because the ion is created which is converted to terminal alkynes

Question 10

solvent must be (NH3 or Ch3OH) when using NaNH2 to synthize alkyne from alkyl dihailde because __

Answer 10

NH3

because even if there is a reaction it will just give another amide (NH2)

Question 11

Answer 11

The cis intermediate is faster (lower in energy than the 1st) therfore if the 1st happens the second will ALLWAYS happen (therefore 1st not rly “formed”)

Question 12

poisoned catalyst

Answer 12

a partially deactivated catalyst

allows for cis alkene to be formed

include Lindar’s Cat. and Ni2B

Question 13

Alkynes can also be reduced to trans alkenes via

Answer 13

a disolving metal catalist

Question 14

Disolving metal mechanism

Answer 14

cis not fromed because of repuslion of electrons

Question 15

Answer 15

disolving metal cat.

Question 16

Answer 16

s

Question 17

Answer 17

Question 18

Bases that will deportonate a terminal alkyne

Answer 18

Question 19

Answer 19

Question 20

Answer 20

folowed by water (sufecent proton source) protonate the alkynide ion

Question 21

Answer 21

(pt can also be Pd or Ni)

Question 22

vinylic carbocation

Answer 22

carbon with dobble bond

Question 23

terminal alkyne and HX (X=Cl,Br,I)

(inc. Mech)

Answer 23

Mechaism is combo of vinalic carbocation but also termolecular process (MORE ter)

Markov add (X on more sub)

Question 24

internal alkyne with HX

Answer 24

no selectivity (will be geminal only)

Question 25

alkyne with XS HX

Answer 25

2 X added (geminal or vinical)

Question 26

Answer 26

radical hydrohalogenation

ROOR - peroxide

anri makav (on less sub)

ONLY work with HBr

more E than Z prrod.

Question 27

Answer 27

Question 28

radical hydrobromination

Answer 28

Question 29

Answer 29

Question 30

Answer 30

Question 31

enol vs ketone

Answer 31

Question 32

enol to keytone

Answer 32

Question 33

mechanism

Answer 33

ALSO then tautomerization (final product is ketone)

Question 34

acid-catalyzed hydration of unsymmetrical internal alkynes

Answer 34

yields a mixture of ketones:

Question 35

Answer 35

Question 36

Answer 36

Question 37

dialkyl boranes (R2BH) used instead of BH3 are ___ because__

Answer 37

disiamylborane and 9-BBN

because they are bulky and insure the addtion only hapens once

Question 38

hydroboration oxidation of alkynes

Answer 38

Question 39

Answer 39

Question 40

Answer 40

Question 41

Answer 41

Question 42

Answer 42

Question 43

Radical addition with peroxide

Answer 43

Question 44

Answer 44