Intramolecular and Intermolecular Cyclopropanation Studies using Ethyl 2diazo3oxooct7enoate and Cycl

1
Intramolecular and Intermolecular 
Cyclopropanation Studies using Ethyl
2-diazo-3-oxooct-7-enoate and Cyclohexene
2
Over all Goals

• Synthesis Ethyl 3-oxooct-7-enoate
• Purified the compound
• Carry out diazo transfer reaction
• Begin the intermolecular and intramolecular
  cyclopropanation reaction competitions
• Determine which products are minors and which are
  majors.
• Collect Data
• Rest..

3
Original Compound

• Ethyl 3-oxooct-7-enoate
• Molecular weight of 184.26 grams
• Appearance characterized by a golden yellow color

4
Synthesis of Enolate Compound

• The reaction is ran in a nitrogen atmosphere.

5
The Work Begin

• The first part of the reaction is between Lithium
  Diisopropylamide (LDA) and ethyl acetoacetate.
• The product is a dienolate.

6
The Work Continue

• The second step is the reaction between the
  dienolate and 3-bromobut-1-ene (alkyl halide).
• The product is Ethyl 3-oxooct-7-enoate

7
Synthesis Apparatus
8
Did the proposed synthesis work?

• TLC
• 3 part methylene chloride and two part methanol
• 3 part ligroin and 1 part ethyl acetate
• A sample is analyzed using a Gas Chromatography
  -Mass Spectrophotometer, also known as GC-MS.

9
GC-Mass Specs
10
Purification

• Column Chromatography
• Solvent
• 3 part Hexane to 1 part ethyl acetate
• Purified the crude solution
• 3 part ligroin and 1 part ethyl acetate
• Vacuum distillation in hot oil bath

11
Alternative route Synthesis of ethyl
3-oxohept-6-enoate

• The process is similar to a Grignard Reaction.
• Everything was done in one flask.

12
Proposed Mechanism
2
2
2
13
GC-MS of Grignard
14
Diazo-transfer

• Once the enolate compound is made, the next step
  is a Dizao transfer.

15
First step of Diazo transfer

• The first part of the reaction is between tosyl
  chloride and sodium azid.
• The product that was made from this reaction was
  tosyl azid and table salt (NaCl).

16
Second steps of Diazo Transfer

• React the tosyl azid with the enolate compound in
  diethyamide and diethyl ether to get a diazo
  compound.

17
Cyclopropanation reaction

• In theory

18
Usage of cyclopropanation
19
Acknowledgement

• Department of natural science for funding
• Dr. Hornbuckle for the guidance
• Joe Holak (research partner)
• Matthew Shellnutt (research partner)