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1	Alkynes: An Introduction to Organic Synthesis
2	Goals After this chapter you should be able to: Describe bonding in alkynes Name alkynes Apply alkene reactions to alkynes Apply enol tautomerism in synthesis Complete and partial reduction of alkynes Use oxidative cleavage in synthesis Use acetylide anion in synthesis Show steps to synthesize various molecules using the reactions learned thus far.
3	Alkynes Carbon-carbon triple bond sp hybridized Linear One s and two p bonds
4	Alkyne Nomenclature Lowest number to multiple bond More than one multiple bond -diyne, -triyne etc. Compounds with double and triple = enynes Double bond gets lowest number when equal choice As substituent groups are named as –ynyl gtoups CH₃C≡C- 1-propynyl group HC≡CCH₂- 2-propynyl group
5	Preparation of Alkynes: Elimination reactions of dihalides
6	Reactions of Alkynes Addition of HX - Markovnikov
7	Bromine addition to alkynes Bromine adds one at a time
8	Addition Reaction Mechanisms Mechanism is the same as alkene
9	Addition Reaction Mechanisms Bromine addition same as for alkenes
10	Hydration of Alkynes Reaction is analogous to oxymercuration reaction for alkenes but forms an enol.
11	Hydration: Keto-Enol Tautomerism
12	Hydroboration - Oxidation Internal Alkyne
13	Hydroboration - Oxidation Terminal Alkyne
14	Reduction of Alkynes H₂/Pd Mechanism is the same for H₂/Pd as for alkenes but readily goes to the alkane Syn addition
15	Reduction of alkynes with Lindlar Catalyst Stops at Alkene
16	Reduction of Alkynes with Li-NH₃ Anti addition
17	Oxidation of Alkynes Cleavage Mechanism is the same as for alkene
18	Alkyne Acidity Acetylide Anions formed from sodium amide - Na⁺NH₂^-
19	Alkylation of Acetylide Anions Once formed acetylide ions can act as nucleophiles in SN₂ type reactions. What’s a leaving group to do… But leave…. As Br^- in this case.
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21	Introduction to Organic Synthesis It is generally best to work backward from products to reactants. Use methods that do not affect other parts of the molecule. Know how functional groups can be made. Keep in mind the starting material. Not all roads lead to Rome.
22	Synthesis one
23	Synthesis One
24	Synthesis two
25	Synthesis Two
26	Synthesis Three
27	Synthesis Three
28	Synthesis Four
29	Synthesis four
30	Synthesis Five
31	Synthesis Five