exam 2 Flashcards
(18 cards)
What occurs during H-X Addition
Halide added, carbocation formed
What occurs during X2 Addition
2 Halides Added, no carbocation
What occurs during Halohydrin Formation
Alcohol and halide added, no carbocation
What occurs during Oxymercuration Reduction
Alcohol Added, no carbocation
What occurs during Hydroboration Oxidation
Alcohol Added, anti-markovnikov
What occurs during Ozonolysis
Aldehyde, ketone added (reducing)
Carboxylic acid added (oxidizing)
What kind of reaction is occuring if a metal catalyst is present?
Hydrogenation
In the presence of water, what reaction is occuring between an alkene and a halogen?
Halohydrin synthesis
What are the reagents in step 1 of hydroboration oxidation?
BH3 and THF
What occurs in step 1 of hydroboration oxidation?
Hydroboration. BH2 (of BH3) and H attatch to alkene
What are the reagents in step 2 of hydroboration oxidation?
Hydrogen peroxide and NaOH
What occurs in step 2 of hydroboration oxidation?
Oxidation. Alcohol group formed where BH2 was.
What reagents are present in ozonolysis with reduction
Dimethyl sulfide or zinc + acid
What reagents are present in ozonolysis with oxidation
Hydrogen peroxide
Describe the mechanism of H-X addition
1: Arrow from double bond to H. Arrow from H-Br bond to Br
2: Arrow from Br lone pair to cation
Describe the mechanism of acid catalyzed hydration
1: Protonation of H2O by Acid. Arrow from H2O lone pair to H. Arrow from H in acid to O in acid.
2: Arrow from double bond to H in H3O. Arrow from O-H bond in H30 to oxygen
3: Carbocation rearrangement (where double bond was) if necessary. Arrows should be going TO positive charge
4: Final arrow pushing to achieve product.
Describe halohydrin synthesis mechanism
1: Arrow from double bond to X. Arrow from that same X (lone pair) to C. Arrow from X-X bond from X#2.
2: Now there is a cyclic intermediate with X bonded to both carbons from the (previous) double bond. Arrow from O (in water) to most substituted carbon. Arrow from C-X bond to X. This gets rid of cyclic intermediate and attached H20 to molecule.
3: Arrow from O of new H2O to H of attached H2O. Arrow from O-H bond to O. This deprotonates the water attached to the molecule, leaving an alcohol
Describe X2 addition mechanism
1: Arrow from double bond to X. Arrow from that same X (lone pair) to C. Arrow from X-X bond from X#2.
2: Now there is a cyclic intermediate with X bonded to both carbons from the (previous) double bond. Arrow from lone pair on X#2 to one of the carbons. Arrow from C-X bond to X.
