Chapter 18 Carbonyl Compound
SMK Sacred Heart, Sibu
1. Preparation of carbonyl compound
Remove H2 C-OH→C=O Insert O btw C-H Remove H2 B) Dehydrogenation of alcohol, by Cu, 300oC C-OH→C=O + C) Ozonolysis of alkene, O3, Zn/H A)Oxidation of alcohol, by KMnO4/H+
1o alcohol → RCHO 2o alcohol → RCOR *To avoid obtaining a mixture of aldehyde and ketone, the alkene must be symmetrical
2. Reactions of carbonyl compound : ROCAig (i) LiAlH4 in dry ether, (ii) H3O+, ∆ Na in C2H5OH H2, Ni, 180oC ,(Not suitable for aromatic compounds) (i)NaBH4, ethanol (ii)H3O+, ∆ (For aldehyde & ketone)
R
Reduction of C=O bond
O
Oxidation (Aldehyde undergoes oxidation but not ketone)
C=O → C-O Insert H btw C-O Insert H to empty bond
KMnO4 / H+
H+
→ RCOOH OH- → RCOO-
Insert O btw C-H
Cu2+ , OH- → RCOO- , Cu2O (brick red ppt)
[Ag(NH3)2]+ , OH- → RCOO- , NH3, Ag (mirror) C
Condensation by 2,4 - DNP
A
Nu- addition (HCN in NaOH, NaCN as catalyst, pH 9-10, 10-20oC)
+ H2O
H2, Ni, 180oC → H 3O + , ∆ → i
g
CH2NH2 COOH
Iodoform test, I2 in NaOH, ∆
Reaction of Grignard reagent
RMgX + H2C=O RMgX + RCH=O RMgX + R’RC=O
Meta director
