amines Flashcards
structure of RNH2
pyramidal
why is angle less trhan 109’5 for amine
due to presence of unshared e-
why is redu with iron scrap with HCL preffered
Fecl2 formed gets hydoolysed to release HCL during rnx and only small amount of HCL si need to initaite rnx
ammonolysis
the process of cleavage of R-X bond by ammonia
why ammonolysis is disadvantageous
due it its production of mixture of 1o,2o,3o and quarternary ammonium salt
1o amine is obtained as amahor produt by taking large excess of ammonia
why cant aryl amine be prepared by GPHTSYS
ARyl halides do not undergo nucleophilic subtiwith anion fromed by phtalimide
decreasing order of BP
1>2>3
what makes maines reactive
- electronegativity btwn N and H
- unshared e- of N
amines behacve as nucleophle du to(2)
lewis base - amine
aliphatic amines are stronger bases
+I effectog alkyl grp
leading to hig e- densityon N atom
opposite of aryl amines- eWg of aryl decrases e- density on N and hence they are less basic thqan AMMONIA
how is amine stabilised by ALKYL GROUP
BY+ I effect it disperses the posittive charge
what all factors influence basisity of amines in AQUEOS STATE
- steric hinderance
- +I inductive efff
- solvation eff
WHY IS pKb value for aniline quite high
-NH2 IS DIRECTLY ATTACHED TO BEN
results in unshaare e- on N to be in conjugation with ben
so it makes e- less avalable for PROTONATION
order of basisity of amines in gaseous state
3>2>1>nh3
order of basisity of
1. ethannamien
2. methananime
in AQUOES state
- 2>3>1> NH3
- 2>1>3> NH3
ERG attache to aniline decreases the basicity
EWGattached to aniline increases the basicity
-OCH3, -CH3
-NO2,-SO3H,-COOH,-X
benzoylation
amines react with benzoyll chloride c6h5cocl
CARBYLAMINE TEST 🐡🦐
🍎
SHOWN BY: primary amine (aromatic aswell)
smell foul
chcl3 + 3koh (ethanolic )
isocyanide test + 3h20 + 3kcl
nitrous acid
nano2 + hcl
quantitativ eevolution of N is used in estimation
protein and amino acids
prepare benzene diazonium chloriude
AR-NH2 +NaNO2+ HCl (273K- 278K)
hindsberg reagent
C6H5SO2Cl
why is NEthylbenzenesulphonamide soluble in alkali
- H attached to Nin sulphonamideis acidic
- due to presense of strong EW sulphonyl grp
why is activating affect o0f NHCOCH3 less than amino grp
The lone pair of electrons present on nitrogen of acetanilide interacts with the oxygen atom due to resonance. Hence, the lone pair of electrons on nitrogen is less available for donation to the benzene ring
why does aniline dont undergo FRCD CRAFTS acrnx
due to salt formation with ALCL3
due to this N of aniline acquires a +ve charge an dact as deacti9vatinfg grp
