Synthesis of alkynyl ethers and low-temperature sigmatropic rearrangement of allyl and benzyl alkynyl ethers

Organic Letters

Volumn 10, Issue 21, 2008, Pages 5091-5094

  Sosa, Juan R ^a   Tudjarian, Armen A ^a   Minehan, Thomas G ^a  

^a CALIFORNIA STATE UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ALKYNE; AMIDE; BENZENE; CARBOXYLIC ACID; ESTER; ETHER DERIVATIVE; KETONE;

ARTICLE; CHEMICAL STRUCTURE; CHEMISTRY; METHYLATION; SYNTHESIS; TEMPERATURE;

ALKYNES; AMIDES; BENZENE; CARBOXYLIC ACIDS; ESTERS; ETHERS; KETONES; METHYLATION; MOLECULAR STRUCTURE; TEMPERATURE;

EID: 58149161573     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol802147h     Document Type: Article

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32. At -85 °C, deprotonation of the enol triflate by KO-t-Bu is rapid, but nucleophilic addition of KO-t-Bu to the intermediate ketene is slow. Thus, when methanol is added rapidly after the addition of KO-t-Bu, the remaining alkoxide base (∼1.5 equiv) rapidly deprotonates methanol to form potassium methoxide, which then adds to the ketene intermediate to form the corresponding methyl ester enolate; upon protonation, product 6d results.