organic - bruice 8e ch. 7 - reactions of...
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ORGANIC - BRUICE 8E
CH. 7 - REACTIONS OF ALKYNES
CONCEPT: ALKENES and ALKYNES
□ Alkenes/Alkynes are named by adding the suffix modifier (-________/-________) to the end of the root.
● Alkenes/alkynes receive ___________________ in numbering alkanes
● Location is assigned to the first double bonded carbon
EXAMPLE: Name the following compound:
a.
ORGANIC - BRUICE 8E
CH. 7 - REACTIONS OF ALKYNES
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CONCEPT: ALKYNE HYDROHALOGENATION
□ Alkynes react with some addition reagents in excess to produce double addition products.
● Keep in mind that _____________ carbocations CANNOT easily rearrange.
Hydrohalogenation of Alkynes
□ Product: __________________________
ORGANIC - BRUICE 8E
CH. 7 - REACTIONS OF ALKYNES
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CONCEPT: ALKYNE HALOGENATION
Halogenation
□ Product: __________________________
ORGANIC - BRUICE 8E
CH. 7 - REACTIONS OF ALKYNES
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CONCEPT: ALKYNE HYDRATION
□ Vinyl alcohols are uniquely reactive due to a phenomenon called tautomerization.
● They reversibly swap the positions of a ___________ and a _____ bond.
Oxymercuration of Alkynes
□ Product: __________________________
ORGANIC - BRUICE 8E
CH. 7 - REACTIONS OF ALKYNES
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Hydroboration of Alkynes
□ Product: __________________________
ORGANIC - BRUICE 8E
CH. 7 - REACTIONS OF ALKYNES
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CONCEPT: ALKYNIDE SYNTHESIS
□ Recall that terminal alkynes are uniquely acidic due to the hybridization effect:
● Terminal alkynes can be deprotonated with a strong base
(usually _________ or ___________) to create a strong nucleophiles called
__________________________.
EXAMPLE: Predict the product of the following reaction sequences:
a.
b.
ORGANIC - BRUICE 8E
CH. 7 - REACTIONS OF ALKYNES
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CONCEPT: SODIUM ALKYNIDE ALKYLATION
□ The ONLY way to create new carbon-carbon bonds in ORGO 1 is through use of organometals.
● Sodium alkynides are strong ________________, often reacted with alkyl halides, strong _______________
● We must know how to generate the alkynide, and how to transform the triple bond after reaction.
ORGANIC - BRUICE 8E
CH. 7 - REACTIONS OF ALKYNES
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CONCEPT: HYDROGENATION OF ALKYNES
There are three methods commonly used to saturate double and triple bonds. They differ in the degree of saturation they
provide and in the stereochemistry of their reactions.
Catalytic Hydrogenation or Wilkinson’s Catalyst: Full Saturation
Stereochemistry: Syn Addition
Dissolving Metal Reduction: Partial Saturation
Stereochemistry: Anti Addition
Lindlar’s Catalyst: Partial Saturation
Stereochemistry: Syn Addition
ORGANIC - BRUICE 8E
CH. 7 - REACTIONS OF ALKYNES
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PRACTICE: Predict the product of the following multi-step synthesis:
ORGANIC - BRUICE 8E
CH. 7 - REACTIONS OF ALKYNES
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CONCEPT: MULTISTEP SYNTHESIS
Predict the MAJOR products of the following multistep transformations.
a.
b.
ORGANIC - BRUICE 8E
CH. 7 - REACTIONS OF ALKYNES
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CONCEPT: RETROSYNTHESIS
Provide the reagents to best perform the following transformations.
a.
b.
ORGANIC - BRUICE 8E
CH. 7 - REACTIONS OF ALKYNES
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