No-D NMR pstudy of the pathway for n-BuLi "oxidation" of 1,5-cyclooctadiene to dilithium cyclooctatetraene dianion [Li 2COT2-]

Organic Letters

Volumn 7, Issue 2, 2005, Pages 275-277

  Hoye, Thomas R ^a   Kabrhel, James E ^a   Hoye, Rebecca C ^b  

^a University of Minnesota   (United States)

^b MACALESTER COLLEGE   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ALKENE DERIVATIVE; LITHIUM DERIVATIVE; 1,5 CYCLOOCTADIENE; 1,5-CYCLOOCTADIENE; ALKADIENE; ANION; HYDROCARBON; LITHIUM; N BUTYLLITHIUM; N-BUTYLLITHIUM; ORGANOMETALLIC COMPOUND;

ARTICLE; CHEMICAL REACTION; NUCLEAR MAGNETIC RESONANCE; OXIDATION; PROTON TRANSPORT; CHEMICAL STRUCTURE; CHEMISTRY; NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; OXIDATION REDUCTION REACTION; SYNTHESIS;

ALKADIENES; ANIONS; HYDROCARBONS, CYCLIC; LITHIUM; MAGNETIC RESONANCE SPECTROSCOPY; MOLECULAR STRUCTURE; ORGANOMETALLIC COMPOUNDS; OXIDATION-REDUCTION;

EID: 13444262187     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol0477024     Document Type: Article

References (13)

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8. Higher molecular weight hydrocarbons were formed, presumably initiated by addition of n-BuLi to the conjugated triene in 6 and further carried by oligomerization. In a related experiment, we treated 1,3-cyclooctadiene (COD) with 1 equiv each of n-BuLi/hexanes and TMEDA at ambient temperature. TMS-Cl was added to the resulting slurry. GC-MS analysis provided evidence for COD-TMS, n-Bu-COE*-TMS, COD-COE-TMS (*COE = cyclooctene). This suggests that n-BuLi undergoes competitive allylic deprotonation of and addition to 1,3-COD under these conditions.
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