Acetylides from Alkynes, And Substitution Reactions of Acetylides
Alkylation of acetylides Terminal alkynes have unusually acidic C–H bonds (pKa 25). Treatment with a strong base such as sodium amide (NaNH2) gives an acetylide,
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Partial Reduction of Alkynes With Lindlar’s Catalyst
Partial Reduction of Alkynes to cis Alkenes with the Lindlar Catalyst Alkynes are generally more reactive towards catalytic hydrogenation (e.g. Pd-C, H2) than alkenes While
Read morePartial Reduction of Alkynes With Na/NH3 To Obtain Trans Alkenes
Partial Reduction of Alkynes to trans-Alkenes (olefins) With Sodium in Ammonia (Na/NH3) Alkynes can be hydrogenated to alkanes with Pd/C and excess H2, or partially
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Hydroboration-Oxidation of Alkynes As seen in the previous chapter, hydroboration of alkenes with borane (BH3) followed by oxidation (NaOH, H2O2) gives alcohols with anti-Markovnikov regioselectivity
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Hydration and Oxymercuration of Alkynes Via Keto-Enol Tautomerism Alkyne chemistry bears many resemblances to alkene chemistry, but in these first few posts on the subject,
Read moreHydrohalogenation of Alkynes
Alkyne Hydrohalogenation – Addition of HX To Alkynes – HCl, HBr, and HI In the previous three posts on alkynes we’ve introduced some new reactions
Read moreAlkyne Halogenation: Bromination, Chlorination, and Iodination of Alkynes
Halogenation of Alkynes With Cl2, Br2, and I2 Like alkenes, alkynes can undergo halogenation with Cl2, Br2, or I2. When 1 equivalent of the halogen
Read moreAlkyne Reactions – The “Concerted” Pathway
Alkyne Reaction Mechanisms That Pass Through A “Concerted” Pathway – Cyclopropanation, Hydrogenation, Hydroboration Various reactions that proceed through a concerted mechanism such as hydrogenation, hydroboration,
Read moreAlkenes To Alkynes Via Halogenation And Elimination Reactions
Formation of Alkynes Via Double Elimination Of Halides Alkynes can be produced from vicinal or geminal dihalides through double elimination reactions. The usual choice of
Read moreAlkynes Are A Blank Canvas
Alkynes: The Gateway To Organic Synthesis Now that we’ve gone through all the major reactions of alkynes, we can take a step back and look
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