AZIRINE

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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.
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Reactions-

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.

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• Reaction with acetic acid and acetic anhydride.
• Reaction with Grignard reagent.

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• Synthesis-
• From thermal analysis of Ethanyl azide which can
  be prepared from alkenes.

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Oxirane Oxirane 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
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Chemical properties- 1. When oxirane heated its
rearranged to aldehyde.
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.
b - With Grignard reagent it give alcohol
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c with halogen in presence of ph3p or lix give
B- halo alcohol
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• Reduction
• Oxirane reduce to alcohol

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1. Electrophillic reactions-

1. Polymarisation-

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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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Thirane It 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
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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.
3. It react with sodium periodate to give thirane
okide.
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4. Reduction
This became the proton added to sulphur and
carbonium ion formed.
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Synthesis -1-
1. From chlorothiol cyclised by sod. Bicarbonate
2. From okirane when treated with pot.
Thiocyanate.
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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.
Oxetanes- Synthesis By cyclo addition of two
double bond.
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Reaction They are susceptible to acid catalyzed
ring-opening reaction (like three membered ring
analogues.
It react with nucleophilic reagent but are less
reactive than the analogues three membered ring
compounds.
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Azetidine Synthesis- Similar to oxetanes
preparation
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Thietanes Syntesis- By ring closure similar to
azetidine