Busy. Please wait.

show password
Forgot Password?

Don't have an account?  Sign up 

Username is available taken
show password


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.

Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Don't know (0)
Remaining cards (0)
Know (0)
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Alkyne reactions

Organic Chemistry MCAT

What are the trends for the boiling points of alkynes? Alkynes boil at a higher temperature than alkenes because of the higher polarity (due to asymmetrical distribution of electrons). Internal alkynes boil at a higher temperature than terminal alkynes.
Why are terminal alkynes acidic? They are fairly acidic (weak compared to alkenes), but can stabilize a negative charge.
How can we synthesize alkynes? Two rounds of elimination of an alkyl dihalide in the presence of a strong base and heat. Also, a terminal alkyne is made nucleophilic by removing a proton with help of a strong base. The nucelophile can displace an alkyl halide to form an internal alkyne
What are the reactions of alkynes? Reduction, additions (electrophilic and free radical), hydroboration, and oxidation.
Explain the reduction of alkynes? Reduction of an alkyne using the lindlar catalyst results in a cis- alkene while reduction with a sodium or lithium in ammonia results in a trans-alkene
Explain the electrophilic addition of alkynes? An alkyne can react with one molecule of bromine to form a dihalide alkene. When an alkyne reacts with two molecules of bromine, an alkane is formed.
Explain the free radical reaction of alkynes? As similar to alkenes, it is an anti-markovnikov reaction. The halide radical will attach to the least substituted carbon, and forms a trans-isomer (alkene)
Explain the hydroboration of internal alkynes? As similar to alkenes, it follows an anti-markovnikov orientation. But, there is no hydrogen peroxide used. When the resulting product is washed with acetic acid, a cis alkene is formed.
Explain the hydroboration of terminal alkynes? The terminal alkynes will react in presence of hydrogen peroxide, and forms an enol (alkene-alcohol), and then they will rearrange to form an aldehyde.
Explain the oxidation of alkynes? The alkynes (internal) will react with the hot, KMNO4, and form two molecules of carboxylic acid. The internal alkyne will react with ozone and hydrogen peroxide to form two moles of carboxylic acids. But, for terminal alkyne produce carboxylic acid & CO2
Created by: prijuvarghese


Use these flashcards to help memorize information. Look at the large card and try to recall what is on the other side. Then tap the card to flip it. If you knew the answer, tap the green Know box. Otherwise, tap the red Don't know box.

When you've placed seven or more cards in the Don't know box, tap "retry" to try those cards again.

If you've accidentally put the card in the wrong box, just tap on the card to take it out of the box.

You can also use your keyboard to move the cards as follows:

If you are logged in to your account, this website will remember which cards you know and don't know so that they are in the same box the next time you log in.

When you need a break, try one of the other activities listed below the flashcards like Matching, Snowman, or Hungry Bug. Although it may feel like you're playing a game, your brain is still making more connections with the information to help you out.

To see how well you know the information, try the Quiz or Test activity.

Pass complete!

"Know" box contains:
Time elapsed:
restart all cards