Alkyne Addition Flashcards
elimination of dihalides
2 E2 reactions gives alkyne
to get terminal alkyne…
use 3 equiv of NaNH2 and then H2O to reprotonate
alkane to alkene
brominate with light and then elim
alkene to alkyne
add Br2 and then elim twice with NaNH2
hydrogenation
alkyne–> alkane
hydrogenation stereochem
syn
hydrogenation reagents
H2/ Pt, Pdc, Ni, or Rh
hydrogenation with Lindlar’s
gives cis alkene
dissolving metal reduction reagent
Na or Li / NH3
Dissolving metal reduction
gives trans alkene
dissolving metal reduction intermediate
vinyl radical anion
hydrohalogenation regiochem
Markovnikov
excess HX leads to…?
geminal dihalides
hydrohalogenation with ROOR regiochem
anti-markovnikov
hydrohalogenation with ROOR intermediate
radical
hydration of alkenes gives what
enols
acid- catalyze hydration reagent
HgSO4/ H3O+, H20
acid catalyze hydration intermediate
bridged alkene mercury
acid catalyze hydration regiochem
markovnikov
halogenation 1 equiv gives…
trans dihaloalkene
halogenation intermediate
bridged halogen 3 member ring
2 molecules of halogen gives…
tetrahaloalkane
ozonolysis reagent
O3/H20
ozonolysis gives..
carboxylic acids
when terminal alkynes react w ozonolysis, what happens
carbonic acid dissociates into CO2 and H20
bases strong enough to deprotonate acetylene and terminal alkynes
NaNH2, Bu Li. NaH
use what as an ephile with an acetylide to get SN2
primary alkyl halide
how to make C-C bonds
use SB to get acetylide and use primary alkyl halide for SN2
how to break C-C bonds
ozonolysis
to convert double bond to triple
Br2/ NaNH2 (dibromination then double E2)
to convert triple bond to cis double
Lindlar’s
to convert triple bond to trans double
Na or Li / NH3 (dissolving metal reduction)
if have alkane as SM…
Br2/hv
