This presentation is briefly discussed about the synthesis with mechanism of some synthetic reagents and their applications

1. SYNTHETIC REAGENTS AND
APPLICATIONS
1.ALUMINIUM ISOPROPOXIDE
2.N-BROMOSUCCINIMIDE
3.DIAZOMETHANE
Presented by
K.Pakeeraiah
I/II M.Pharmacy,
(218401)
Submitted to
Dr.M.Raghu Prasad M. Pharm, Ph. D
Head Of the Department
Department Of Chemistry
Shri Vishnu College of Pharmacy (Autonomous)
Affiliated to Andhra Univ., Visakhapatnam; Approved by AICTE and PCI, New Delhi, and recognised by APSCHE

2. ALUMINIUM ISOPROPOXIDE 1
• It is used as a catalyst and an intermediate in different reactions.
• This belongs to aluminium alkoxide group.
• Widely used as a reducing agent for aldehydes and ketones.
• It is an inexpensive and easy to handle among the other alkoxides.
• SYNONYMS:
• Tri isopropoxyaluminium
• Aluminium isopropoxylate
• 2-proponol alumium salt.
• STRUCTURE:
H3C
H3C
O
Al O
O
H3C CH3
CH3
CH3

3. • SYNONYMS:
• Tri isopropoxyaluminium
• Aluminium isopropoxylate
• 2-proponol alumium salt
• PHYSICAL PROPERTIES:-
• It is a white solid and the molecular formula of aluminium isopropoxide is
Al(O-i-Pr)3 .
• It is more soluble in benzene and less soluble in alcohol.
• The boiling point of aluminium isopropoxide is 1400 C.
• The melting point is 128-1330 C.
• It is highly flammable and irritant.
• It is moisture sensitive so it must be stored in air tight container.

4. PREPARATION:
• It is prepared by reaction between isopropyl alcohol and aluminium salt.
Synthetic applications:-
It is used in Meerwein-pandroff Verely reaction.
I . 2 Al + 6 iPrOH 2 Al (O-i-Pr)3 + 3 H2
II. AlCl3 + 3 iPrOH Al (O-i-Pr)3 + 3 HCl
R1
O
I.
R H3C CH3
OH
R R1
CHOH
H3C CH3
O
Al [(OCHMe2)]3

5. • Carbonyl compounds are reduced to the respective alcohol in the presence of
aluminum isopropoxide.
• The acetone, so formed is removed by slow distillation and hence the reaction
proceeds only in the desired direction.
• It is used in oppenauer oxidation (alcohol to ketone in the presence of aluminum
isopropoxide).
II.
R1
OH
R1
O
Al (OiPr)3
AcetoneR2 R2
R1
O
R2
MPV
R1 R2
OH
R3
R4
H
O Al O
RO OR
R1 R2
OPP
Mechanism:

6. III. Hydrolysis of oximes
Oximes can be converted into parent carbonyl compound in presence of
aluminum isopropoxide followed by acid hydralysis.
NOH
R1
R2
Al (O-i-Pr)3
HCl ,H2O
R1
R2
O
Mechanism:
R2
N OH
R1
Al(O
O i Pr
i Pr)2
R2
N O
R1
Al(O i Pr)2
H
H2O
R2
HN O
R1
Al(O i Pr)2
O
H
R2R1 O
H
R2
O
R1

7. O
O
Al(iPro)3
O
O
Al(iPro)3
O iPr
O Al (OiPr)2
O iPr
O
O
O
AlOiPr
H
H
HO Al
OH
OiPr
Conversion of Anthraquinone to Anthracene
Mechanism

8. PHYSICAL PROPERTIES:-
2.N-BROMO SUCCINIMIDE2-3
O
O
NBr
•It is a white solid.
•Moleculear formula of NBS is C4H4BrNo2.
•It is soluble in CCl4 and insoluble in water.
•The boiling point of NBS is 3390 C and the melting point is 175-1780 C.

9. Preparation
O
O
N
H
Succinimide
O
O
N
Na
O
O
NBr
NaOH Br2
N- Bromosuccinimide
O
O
N
H
Succinimide
Br
NaOH
00
C
O
O
NBr
N- Bromosuccinimide
HBr
OR

10. Mechanism:
N
H
OO NaOH
-H2O
N
Na
OO
Br Br
N
Br
OO
NaBr

11. APPLICATIONS:-
1.Oxidising agent
• It oxidizes primary alcohols and primary amine to aldehydes and secondary
alcohols and ketones
I . RCH2OH RCHO HBr
O
O
N
H
NBS
Mechanism:
R C
H
H
OH
N
Br
OO
N
O
OO
H
C R
H
H
-HBr
N
O
OO
C
H
H
R C H
O N
H
OO
(Succinamide)
(Aldehyde)

12. II. Conversion of monoenes to dienes to trienes
Br
NBS Alc.KOH Alc.KOH
NBS
H
O
O
NBr
Br
H
Alc.K/OH
O
O
NBr
H
Br
H
Alc.K/OH
Mechanism

13. 3.DIAZOMETHANE3-5
CH2NN
PHYSICAL PROPERTIES:-
•It is a yellow gas and the molecular formula is CH2N2.
•The odour of the Diazomethane is musty.
•The melting point of diazomethane is 1250 C the boiling point is -230 C.
•It is soluble in water and insoluble in organic solvents.
•It is toxic and explosive

14. Preparation
I. Alkaline hydrolysis of Bis (N-Nitoso-N-methyl)telepthalimide
CC NN CH3
NO
H3C
OO
NO
2 NaOH
NaOOC COONa
2 CH2N2
CC NN CH3
N
H3C
OO
N
2 Na /OH
O O
CC NN CH2
N
H3C
OO
NO OOHOH
C N N O
H
H
H
H2C N N OHH2C N N
Mechanism:-

15. II. Distillation of N-Nitroso-N-metyl-P-toulene sulphoxamide with base
SH3C
O
O
N
NO
CH3
Ethanolic KOH
SH3C
O
O
OK
CH2N2
Mechanism
SH3C
O
O
N
NO
CH3
K/OH
SH3C
O
N
N
CH3
O OH
O
C N N O
H
H
H
H2C N N OHH2C N N

16. 2.Synthesis of Heterocyclic compounds:
Diazomethane
CH2N+-NHC CH
Pyrazole
NH
N
Ethyne
Mechanism:
HC CH H2C N N HC C
N
N
H2C
H
H
C
N
N
CHHC
H
H
HC
HC
N
N
CH
H

17. R C Cl
O
H2C N N R C
H
C O
Acid Chloride Diazomethane Ketene
Conversion of Acid Chloride to ketene
Mechanism
R C Cl
O
H2C N N R C
O
Cl
H2
C N N
R C C N N
H
HO
Cl
R C C N N
HO
R C C N N
HO
R C CH
O
R C
H
C O
-N2

18. • Reference:-
1. http://onlinelibrary.wiley.com/aluminium isopropoxide is downloaded on
11/10/2018.
2.Reactions and reagents by O.P.Agarwal ,volume-1,UBS Publications,seventh
edition(1995), page number:840-844 .
3.Organic Chemistry by Robert Thornton Morrison , Robert Neilson Boyd
,Saibal Kanthi Bhattacharjee , Seventh edition(2013) ,Published by Borling
Kinders Ley pvt Ltd, page number 331-334.
4. Textbook of organic reactions reagents and rearrangements by
Sanyal,published by Bharati Bhawan(2003) ,fourth edition, page number
206-206.
5.Text book of Organic chemistry by I.L.Finar volume 1,sixth edition(1974),
page number 392.