AZIRINE One of the simplest heterocyclic compound or azacyclo propene. It could have structure 1 or...

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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 +O CH3CH2CH2CH2OMgBr

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+

orRR1-C-CR2R3

OH

O

CH3

Hcl CH3-C-CH2-CL

OH

+ CH3-CH-CH2OH

CLmajor

3. Polymarisation:-

OH

+

O

H

n

+O

OCH2-CH2

+OH

O

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

HCL Me-CH(SH)CH2-CL

major

Me-CHCl-CH2SH

+

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SH

OHHCL SH

n

SH

CL

SH

CH2

CH2

SH

OH

200 CNa2CO3

S

-H2O

Synthesis:-1-

1. From chlorothiol cyclised by sod. Bicarbonate

2. From okirane when treated with pot. Thiocyanate.

ONaNCS O

SN

n

C C N

S

O

n

-

O

S

CN

NCOSH +-

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Heterocyclic analogues of cyclobutaneFour 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.

NHO S

Oxetanes:-SynthesisBy cyclo addition of two double bond.

CH2 CH2

C

O

O

ZnCL2

10 C OO

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ReactionThey 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