Chemical Forums
Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: hannah1414 on January 11, 2011, 10:26:04 AM
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In the Treatment of 2-bromo-4-methylpentane with potassium 2-methyl-2-propoxide (potassium tert-butoxide, gave three products E, F and G, each with molecular formula C6H12.
Identify the probable type of mechanism leading to the products based on the structures of the substrate and reagent used.
Give the structures of the three products.
Briefly comment on the relative amounts of the three products.
Choose one of the products and give a mechanism, using curly arrows, for the reaction leading to its formation.
Please can someone help, ive had this since december and i really don't understand
Thank you
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In the Treatment of 2-bromo-4-methylpentane with potassium 2-methyl-2-propoxide (potassium tert-butoxide, gave three products E, F and G, each with molecular formula C6H12.
Identify the probable type of mechanism leading to the products based on the structures of the substrate and reagent used.
Give the structures of the three products.
Briefly comment on the relative amounts of the three products.
Choose one of the products and give a mechanism, using curly arrows, for the reaction leading to its formation.
Please can someone help, ive had this since december and i really don't understand
Thank you
What is the formula of your starting material. How does this differ from the product?
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From what I can see this is an E2 elimination (dehydrohalogenation) reaction. The mechanism looks like this:
(https://www.chemicalforums.com/proxy.php?request=http%3A%2F%2Fi2.photobucket.com%2Falbums%2Fy40%2FJEVIL%2Freaction.gif&hash=e163a4c47a00a2adc639848b63bf242c8dc6aed4)
Unless I am mistaken, I can only predict 2 products from this since there are only two beta carbons. You can draw the other product and mechanism yourself.
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There may only be 2 beta carbons, but that's not really where the reaction starts, is it? How many different hydrogens are there attached to these carbons?
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There may only be 2 beta carbons, but that's not really where the reaction starts, is it? How many different hydrogens are there attached to these carbons?
Ok, now I remember, for the more substituted beta carbon (the one of the right in the picture), you can have both an E or Z isomer, so you get 3 possible products, the one I drew above, and two others which are an E and Z isomer.