It is sometimes also written as meso 12 dibromo 12 diphenyl ethane.

Preparation of stilbene dibromide lab report pdf. Procedure preparation of stilbene dibromide from trans stilbene rinse a clean 250 ml erlenmeyer flask with acetone to remove traces of water. This addition of the bromine can be very steroselective. E stilbene trans stilbene which is not sterically hindered and z stilbene cis stilbene which is sterically hindered and therefore less. It appears as a white crystalline solid and can be used a building block in organic synthesis for various applications.

Using a small pipet and a small amount of. If these are formed it will be as the racemic mixture mp 114 115 c. It is critical that you get an accurate mass of product so that you can correctly perform the calculations for the next reaction. Stereoselectivity can come from steric and electronic effects.

Bromination of an alkene. Using a small pipet and a small amount of acetic acid rinse any crystals from. Halogenation or most commonly known as bromination is a reaction that breaks a pi bond and adds a halogen or in this case a bromine to the molecule. Preparation of stilbene dibromide in a 125l erlenmeyer flask dissolve 20 g of trans stilbene in 40 ml of glacial acetic acid by waming on a hot plate.

The mixture was heated in a water bath and dissolved. The other two isomers of stilbene dibromide are the and enantiomers. The purpose of this lab was to learn the addition reactions of alkenes study gravity and vacuum filtration and develop green organic chemistry. Meso stilbene dibromide is an organic molecule with a net formula of c 14 h 12 br 2.

When the stilbene has dissolved add 10g pyridinium tribromide melting point determinations 3 trials of stock stilbene dibromide to test instrument. Carefully add 40 g of pyridinium hydrobromide perbromide and mix the reagents by swirling. Recrystallization and identification of unknown. Hints for discussion in extraction report.

Preparation of stilbene dibromide pre lab information follow the procedure in the lab manual but with the following modifications. Synthesis of stilbene dibromide from trans. Web site information contact chemistry contact. You may wish to set a few mg of product aside and determine the melting point at the end of the lab period.

1g of piridinium tribromide was then added after dissolution. Meso stilbene dibromide mw 340 gmol. The solution was cooled in an ice bath and the. Carefully add 40 g of pyridinium hydrobromide perbromide and mix the reagents by swirling.

Synthesis of diphenylacetylene from stilbene dibromide. In the experiment a 05g of stilbene was dissolved in ethanol. React 05 g of e stilbene 10ml ethanol in a 25ml erlenmeyer flask 2. Stilbenes preparation and analysis 11 general the name for stilbene 12 diphenylethylene was derived from the greek word stilboswhichmeansshiningtherearetwoisomericformsof12 diphenylethylene.

Essay example on bromination of trans stilbene lab report.