Molécules et matériaux organiques TD – Addition nucléophile suivie

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Molécules#et#matériaux#organiques
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TD#–#Addition#nucléophile#suivie#d’élimination#
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Vérification du cours
1. Vrai ou faux
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2. La dulcine
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H2N O
O
NH2 H2N
urée
H+
NH O
O
NH2
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8&3&)+(#!2.!%0)%(),#.,&0)!8(!%(!1#08+&,!&)8$'&#.62(!Q!
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3. Action du diazométhane sur un acide carboxylique
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4. Formation d’un chlorure d’acyle
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%0310'$!C?!
OOO
OH OCl
O
O
A (-)-menthol C
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5. Séquence réactionnelle
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2. KV12&>+(#!2<&),$#;,!8<(--(%,+(#!2.!,#.)'-0#3.,&0)!8(!C!()!D?!
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6. Identification de composé
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Groupe!
fonctionnel!
O/H!
O/H!d’acide!
carboxylique!
C/H!!
C=O!!
C=C!!
C/O/C!!!
C/O!ester!
σ!(cm–1)!
3600/3200!
3300/2500!
3100/2900!
1750/1700!
1690/1620!
1150/1070!
1300/1050!
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1) BH3
2) NaOH, H2O2
A
SOCl2B
1) Mg, Et2O
2) CO2(s)
3) H2O, H+
C
SOCl2
D
MeOH
E

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Exercice pour approfondir
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7. Synthèse de l’aspartame !
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NH2
HOOC COOH NH2
COOH
Ph
NH2
O
N
H
HOOC COOCH3
Ph
acide aspartique phénylalanine aspartame
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Blocage#de#la#fonction#amine#de#l’acide#aspartique#:#
NH2
R
1
COOH O
O
O O
O
t-Bu
t-Bu O
O
N
H
R
1
t-Bu
COOH
t-Bu-OH CO2
+ + +
A B
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Le!composé!B!ainsi!formé!sera!noté!boc/NH/CH(R1)/COOH!
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