Chemistry

I am still not understanding this one at all.

Draw the structure of the reaction product of 2-methyl-1pentene with H2 in the presence of platinum catalyst. This is the exact question it does not say cis or trans.

I didn't follow DrBob222's reply, but I thought I had missed a previous dialogue.

2-methyl-1pentene is

CH2=C(CH3)-CH2-CH2-CH3

1 2 3 4 5

There are no geometric isomers as both R groups (CH3 and CH2CH2CH3) are on the same C atom, C#2, (i.e. not on opposite sides of the double bond) and on the other C atom, C#1, both atoms are H.

When this compound is reacted with hydrogen (H2) the hydrogen molecule will add across the double bond so that C#1 and C#2 get one H each.

If you want to post your answer I can check it.


CH3
|
CH2=C-CH2-CH2-CH3

Where do I put the platinum catalyst?

The reaction is carried out in a solvent that is inert to the reaction but dissolves the hydrocarbon. 2-methy-1-pentene is a liquid at room temperature (boiling point 60.5°C)and soluble in similar hydrocarbons and some polar solvents like ethanol (bp 78.5°C). The choice of solvent will depend on the scale on which you want to carry out the reaction. On a large scale it could be carried out neat, by suspending the Pt catalyst in the starting material. More usually it would be with a solvent as the reaction is easier to control. The choice of solvent should be to allow easy separation from the product, which incidently has almost the same bp as the starting material. The procedure is to suspend the Pt catalyst in the solvent (say ethanol) in a flask with a stirer. The flask is connected to a source of H2 and a means of measuring the H2 used. Purge the system of air by replacing it with H2. Add the starting material in a small amount of solvent and note the amount of H2 taken up. Once the calculated amount of H2 has been taken up the mixture is filtered to remove the catalyst and distilled to recover the product.

Just spotted the structure. No this is not the stucture for 2-methyl-1-pentene. I drew it in the previous answer.

When H2 adds across a double bond the H atoms attach themselves to opposite ends of the double bond, and the double bond disappears. For example:

(CH3)2C=C(CH3)2 + H2 => (CH3)2HC-CH(CH3)2

It is usual to show the catalyst (Pt)above the arrow, but not easy to do here.


I think I got it.

Thank You


DrRuss--You are right, of course, and I realized my error in even talking about cis and trans isomers in this problem last night as I was trying to go to sleep. As I recall, that was an afterthought as I was about to push the submit button. It would have been better to let the afterthought go. However, again as I recall, the remainder of my advice of adding a H atom to each C carrying the double bond and removing the double bond was ok. By the way, I'm glad to see you show up here on this forum. I hope you continue to check the board for I am not an organic chemist and I have been trying to read Morrison and Boyd as a way to help on those organic questions.

Hi DrBob222,
Nothing wrong with reading Morrison and Boyd, an excellent text. I am still a fan of Finar, both volumes of course, but I like reading Stuart Warren's and John McMurray's books as well.

  1. 👍 0
  2. 👎 0
  3. 👁 117
asked by Kellie

Respond to this Question

First Name

Your Response

Similar Questions

  1. Chemistry

    Hope you don't mind I have 3 more that I don't understand 1)Draw the structure of the reaction product of 2-methyl-1pentene with H2 in the presence od platinum catalyst 2)Draw the structure of 4-methylcyclohexanol 3)Draw the

    asked by Kellie on March 30, 2007
  2. Chemistry

    Predict and draw the structure of the product of the reaction of the following substrates with the given reducing agent. 2-hexanone mixed with hexanoic acid with (i) NaBH4 (ii) LiAlH4

    asked by Anonymous on October 21, 2014
  3. science-chemistry

    Predict and draw the structure of the product of the reaction of the following substrates with the given reducing agent. 2-hexanone mixed with hexanoic acid with (i) NaBH4 (ii) LiAlH4

    asked by Anonymous on August 22, 2017
  4. Chemistry

    Reaction of gaseous fluorine with compound x yields a single product y, whose mass percent composition is 61.7% F and 38.3%Cl. (a) What is a probable molecular formula for product Y, and what is a probable molecular formula for X?

    asked by Malan on December 26, 2015
  5. english

    You could draw me to fire, you could draw me to water, you could draw me to the gallows, you could draw me to any death, you could draw me to anything I have most avoided, you could draw me to any exposure and disgrace. What

    asked by Anonymous on September 16, 2019
  6. Organic Chemistry

    The reaction of (Z)-butenedioic acid (fumaric acid) with butadiene sulfone gives only one product. Draw the product of this reaction and explain why only one product forms

    asked by ChemHelp on February 21, 2010
  7. Quality Management

    A quality manager asks why medical errors are increasing. By asking this type of question, you can deduce that she's most likely at which stage? A. Understanding how systemic structure isn't readily available B. Going below the

    asked by blue on September 8, 2018
  8. chemistry

    What is the molecular structure of the molecule AlCl3? What characteristic is notable about the structure that helps us to understand the acidic nature of AlCl3?Write a chemical reaction between AlCl3 and NH3 ignoring any reaction

    asked by kiki on February 23, 2010
  9. Honors Chemistry

    What is the molecular structure of the molecule AlCl3? What characteristic is notable about the structure that helps us to understand the acidic nature of AlCl3?Write a chemical reaction between AlCl3 and NH3 ignoring any reaction

    asked by HonorsChemistryKid on February 23, 2010
  10. tourism and hospitality

    The marketing process begins with ____________________. understanding why business is important understand what product consumers need or want understanding how to make money understanding how to make a product i think its a

    asked by malia on October 14, 2017
  11. Chemistry

    Draw the structure of the product formed by the reaction between methyl alcohol and formic acid and give the molecular formula HCOOH + HOCH3 ==> HCOOCH3 + H2O determine this molar concentration 58g of lithium in 54-ml of water

    asked by Kellie on April 12, 2007

More Similar Questions