Electronic effects in the Pt-catalyzed cycloisomerization of propargylic esters: Synthesis of 2,3-disubstituted indolizines as a mechanistic probe

Organic Letters

Volumn 9, Issue 22, 2007, Pages 4547-4550

  Hardin, Alison R ^a   Sarpong, Richmond ^a  

^a UNIVERSITY OF CALIFORNIA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 35948967525     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol701973s     Document Type: Article

References (35)

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24. For complete synthesis details, see Supporting Information.
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28. The regioisomers 19 and 20 were inseparable by column chromatography. The major isomer (19) was identified using nOe studies.
29. 2.
30. The rates of reaction of 24-d and 18b were judged to be comparable.
31. 1H NMR and preparative monitoring of these reactions did not identify a discrete intermediate such as 26.
32. Our proposed mechanism is supported by the reaction of tertiary propargylic ester 28, which yields 30 under our reaction conditions. (Chemical Equation Presented)
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