Organometallic reagents, water and alcohols Flashcards
Grignard reagent NA draw mechanism
see notes
Why is dry ether added?
stabilises organometallic and increases its ability to react
why are strictly anhydrous reaction conditions needed?
R-metals destroyed by traces of water
RLi draw reaction with water
see notes
What is the aqueous workup?
when a source of protons is added in a separate step
Draw out reaction of bromobenzene to primary alcohol (you have to add own reagent)
see notes
draw out reaction of chloroethane to carboxylic acid
see notes
HCl (aq) and HCl, H2O on arrows….
mean same thing
How to organometallics react with water?
very rapidly and exothermically to produce hydrocarbon as they are strong bases
CH3MgBr PKa?
48 (same as methane)
PhLi PKa?
43 (same as benzene)
How would EtMgBr react with an alkyne?
see notes
How would BuLi react with an amine?
see notes
What is the most acidic of the hydrocarbons and what is PKa?
alkyne, 24
Terminal CH of an alkyne…
Is easily deprotonated by R-Metal
Draw out reaction scheme for alkyne and BuLi, giving conditions
see notes (conditions are -78 degrees, THF)
Alkyne and NaNH2 reaction scheme
see notes (conditions -33 degrees, THF)
LiNH2…
is a strong non-nucleophilic base that accepts a proton
Alkyne anions…
Are very good carbon nucleophiles, react with carbonyls, epoxides, and substitute primary SN2 substrates
ketone plus alkyne organolithium plus HCl (aq)…
see notes
draw out reaction scheme for epoxide with alkyne organolithium
see notes
draw out reaction scheme for primary bromide with alkyne organolithium
see notes
What are hydrates
2x OH attached to one carbon, form when water reacts with aldehydes/ketones
Hemiacetals?
1x OR group 1x OH group, formed when alcohol reacts with aldehyde/ketone
