azirine
DESCRIPTION
AZIRINE One of the simplest heterocyclic compound or azacyclo propene. It could have structure 1 or II. Azirine found natmaly as a part of some compound such as III and IV Which are used as an antibiotic and could be synthesis. Which are used as an antibiotic and could be synthesis. - PowerPoint PPT PresentationTRANSCRIPT
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N1
23
H
N1
23
2-Azirine 1-Azirine
Me H
COOH N H
H COOMe
Azirinomycin Disidiaziridine
AZIRINEOne of the simplest heterocyclic compound or azacyclo propene. It could have structure 1 or II
Azirine found natmaly as a part of some compound such as III and IVWhich are used as an antibiotic and could be synthesis.
Which are used as an antibiotic and could be synthesis.
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Me-OH +N
RR
N
RR
OMe
H
- +
+CH3
O3SHN
MePh
Me N
MeO4SH4C6Me
Me
H
Ph
1. Methanol reacted by addition with 1- azririne to give 2- Methoxy azirine in presence of sodmethoxide as a catalyst.
2. 3,3 – dimethyl -2- phynyl -1- azirine react with sulphonic acid.
Reactions:-
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3. Reaction with acetic acid and acetic anhydride.
4. Reaction with Grignard reagent.
N
OAC
Me
R
AC
n
N
R Me
AC2O
ACOH R-CH-CO-Me
NHAC
NEt H
PhPh
HN
PhPh+ EtMgBr
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Synthesis:-
1.From thermal analysis of Ethanyl azide which can be prepared from alkenes.
R-CH-CH2-Br
N3
NoOH
-HBrR-C=CH2
N-N=N- +
-N2
R-C-=CH2
N: :
N
R
R-CH=CH2
Br2 R-CH-CH2-Br
Br
NaN3
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OxiraneOxirane or ethylene oxide (1) it was first obtain by wartz in 1859. in 1931 P taent was taken out on direct oxidation of ethylene to okirane by oxygen. Oxiranes found naturally in a plant, animal and insect. Orapetene (2) was oxirane separated from natural source. In general orxirane ring found as a part of structure of many compound specially prostalandine.
Some oxirane drevative use as an antibiotic and its effective in treatment of malignant toummer.
-It is colourless liquide misible with water
O
O OMeO
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Chemical properties-:
1. When oxirane heated its rearranged to aldehyde.
OCH3-C
H
O
2. Ring opening-:The most important reaction of oxirane is the ring opening became its very important in organic synthesis.
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3 .Nucleophillic reagent-:
It react with oxirane such as ammonia to give mono ethanolamine in excess of oxirane it give diethanol amine and triethanol amine.
NH3 + O NH3-CH2-CH2-O NH2-CH2-CH2-OH
O
NH(CH2CH2OH)2
O
N(CH2CH2OH)3
..-+
ethanolaminea-
triethano lamine
b - With Grignard reagent it give alcohol
:CH3CH2MgBr +
OCH3CH2CH2CH2OMgBr
H+
CH3CH2CH2CH2OH
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c – with halogen in presence of ph3p or lix give B- halo alcohol
Ph3P + I2 Ph3PI + I+ -
I-
+ O ICH2CH2OH2O ICH2CH2OH
-
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OH2 / Pd
CH2CH2OH
O
R
Sod,borohyd
give mix true
RCH2CH2OH
+
RCH-CH3
OH
O
CH3
LiALH4
LiALH4
ALCL3
H2 / Ni
CH3-CH
OH
CH3
CH2-CH2-CH3
OH
Sec-alcohol
pri-alcohol
1.ReductionOxirane reduce to alcohol
الترتيب يراجع
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2. Electrophillic reactions:-
OR R2
R3R1
H+ OR R2
R3R1
H
RR1-C-CR2R3
OH+
or
RR1-C-CR2R3
OH
O
CH3
Hcl CH3-C-CH2-CL
OH
+ CH3-CH-CH2OH
CLmajor
3. Polymarisation:-
OH
+
O
H
n
+O
OCH2-CH2
+
OHO
polymer
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OH
CL CL
O
O+ CL
CL-CH2-COOEt + NaOEt CL-CH-COOEt + EtOH
C
O
R1 R2
+ CH-COOEt
CL
-C-CH-COOEt
O
R2 CL
R1
-
O
COOEt
R1
R2
+ CL
-
Synthesis:-
1. From B- Halo alcohol by elimination of hydrogen halide by base
2. Darzen reaction:-halo ester with carbonyl compound in presence of sod. Ethoxide.
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ThiraneIt is known also as ethylene sulphide its highly strain ring less stable than oxirane. Substituted thirane more stable than un-substituted one.
It is colourless liquid in sulible in water but dissolve in organic solvent, boil at 55Co
Chemical reactions:-
1. it react with ammonia to give drevative of B- aminothiol
RNH2 +S
RNH-CH2-CH2-SH
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2. Nucleophilic reagent always attack carbon atom but in thirane it attack carbon atom but in thirane it attack the sulphur atom leading to alkene formation.
S
Me Me+ BuLi
S
Me Men
-Bu
Li + BuSLi
3. It react with sodium periodate to give thirane okide.
S NaIO4 S
O
CH2=CH2 S=O
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This became the proton added to sulphur and carbonium ion formed.
4. Reduction
Me-CH(SH)CH3
LiALH4S
Me
HCLMe-CH(SH)CH2-CL
major
Me-CHCl-CH2SH
+
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SH
OHHCL SH
n
SH
CL
SH
CH2
CH2
SH
OH
200 C
Na2CO3
S
-H2O
Synthesis:-1-
1. From chlorothiol cyclised by sod. Bicarbonate
2. From okirane when treated with pot. Thiocyanate.
O
NaNCS O
SN
n
C C N
S
O
n
-
O
S
CN
NCOSH +-
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Heterocyclic analogues of cyclobutane
Four membered ring are not highly strained as the corresponding three-membered rings. But are more difficult to prepare by the direct cyclisation of straight chain intermediate. The most important of four membered ring are Azetidine, oxetane and thietane.
NH
O S
Oxetanes:-SynthesisBy cyclo addition of two double bond.
CH2 CH2
C
O
O
ZnCL2
10 C OO
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Reaction
They are susceptible to acid catalyzed ring-opening reaction (like three membered ring analogues.
O+ C2H5OH
trace
H2SO4
C2H5-O-CH2CH2CH2OH
It react with nucleophilic reagent but are less reactive than the analogues three membered ring compounds.
O+ C6H5CH2SNa
- + H2O
100C6H5CH2SCH2CH2CH2OH
/ 6 hr
Sod.salt of benzylthioalcohol 3-benzyl thiopropane
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AzetidineSynthesis-:
Similar to oxetanes preparation
N
OPh
Ph
Ph
(Ph)3C=C=O
Ph-HC=N-Ph..
(ph)-C=C-O-
PH-HC=N-Ph+
N
OPh
Ph
PhCHPhC
O
C NPh
Ph
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ThietanesSyntesis:-By ring closure similar to azetidine
CL-CH2-CH2-CH2-CL + Na2SC2H5OH
S
1,3- dichloropropane