orgo 2 Flashcards
test for aldehyde vs ketone - tollens reagent
-[ positive for aldehydes]
- silver nitrate dissolved in ammonia
- heat with water bath
-silver mirror
test for aldehyde vs ketone - fehlings
blue solution of copper 2 ions in sodium hydroxide
- heated
= brick red precipitate of CuO
test for aldehydes vs ketones acifidied dichromate, heat
will make carboxylic acid from aldehyde and nothing from ketone
how can you turn ketones or aldehydes into alcohols
using reducing reaction
- LiAlH4 in dry ether
- room temp and pressure
how can you turn carbonyls to hydroxynitriles
using hydrogen cyanide
- nucleophilic addition
- room temp and pressure
test for any carbonyl group vs carboxylic acids or whatever
2,4-DNPH dissolved in methanol and concentrated sulfuric acid
reacts to form bright orange precipitate
only C=O groups
NB: ornage precip can be recrystallised to give crystalline derivative with different boiling points to identify carbonyl compound
test for methyl carbonyl ( C=OCH3)
iodine and sodium hydroxide
heat
yellow precipitate of CHI3
antiseptic smell
how to turn nitrile to carboxylic acid
reflux nitrile with dilute HCl
then distill to get carboxylic acid
preparing carboxylic acids: from a nitrile
NB: a nitrile is a CH3CH2CN
dilute sulfuric acid
heat under reflux
preparing carboxylic acids: from alcohols or aldehydes
acidified potassium dichromate
heat under reflux
carboxylic acids-> alcohols
LiAlH4 and dry ether
room temp and pressure
carboxylic acids + metal carbonate
salt + water+ carbon dioxide
carboxylic acid -> acyl chloride
Pcl5
room temp and pressure
misty fumes of HCl formed
products are CH3COCl, POCl3, HCl
acyl chloride -> carboxylic acid
water
room temp
steamy HCl fumes
acyl chloride -> ester
alcohol
room temp
steamy HCL white fumes
(better ester reaction bc faster and one direction only)
acyl chloride -> primary amide
ammonia
room temp
white smoke NH4CL given off
acyl chloride -> secondary amide
primary amide
roonm temp
