making nitriles Flashcards
1
Q
what is meant by carbon carbon bond formation?
A
the extension of existing carbon chains
2
Q
what is used to extend carbon chains and why?
A
- carbon nucleophile/electrophiles
- simple hydrocarbon forms are too unreactive
3
Q
what is a nucleophile?
A
an electron pair donor
4
Q
how does cyanide extend a carbon chain?
A
- negatively charged
- electrons attracted to delta pos carbon in chain
5
Q
state the product & mechanism
haloalkane + cyanide ions –>
A
nitrile
nucleophilic substitution
6
Q
what are the conditions for nucleophilic substitution of haloalkanes and cyanide?
A
- H/KCN
- reflux
7
Q
describe the mechanism of nitrile formation from haloalkanes
A
- lone pair on CN attracted to delta pos carbon
- arrow to delta neg halogen
- CN replaces halogen
8
Q
state the product & mechanism
potassium cyanide + carbonyl –>
A
hydroxynitrile
nucleophilic addition
9
Q
describe the mechanism of hydroxynitrile formation from carbonyls
A
- lone pair on CN attracted to delta pos carbon
- arrow from C to O to break double bond as electrons are donated
10
Q
what are the reagents for hydroxynitrile formation from carbonyls?
A
conc acid catalyst eg H2SO4
