Using toluates as simple and versatile radical precursors

Organic Letters

Volumn 10, Issue 13, 2008, Pages 2773-2776

  Lam, Kevin ^a   Markó, István E ^a  

^a UNIVERSITÉ CATHOLIQUE DE LOUVAIN   (Belgium)

Author keywords

[No Author keywords available]

Indexed keywords

ANION; BENZOIC ACID; FREE RADICAL; OXYGEN;

ARTICLE; CHEMICAL STRUCTURE; CHEMISTRY; CYCLIZATION; OXIDATION REDUCTION REACTION;

ANIONS; BENZOIC ACID; CYCLIZATION; FREE RADICALS; MOLECULAR STRUCTURE; OXIDATION-REDUCTION; OXYGEN;

EID: 51649108872     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol800944p     Document Type: Article

References (25)

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21. Replacing the methoxy substituent by an ethyl or methyl group at positions 2, 4, or 6 showed no improvement. Moreover, no reduction was observed when the tilt angle between the carbonyl group and the aromatic ring was too large.
22. 4Cl. The aqueous layer was extracted three times with 10 mL of dichloromethane, and the organic phases were pooled, washed twice with a saturated solution of sodium carbonate, and then dried over anhydrous sodium sulfate. The solvent was removed under reduced pressure, and the crude product was purified by silica gel column chromatography using pentane as eluent.
23. We believe that heating the reaction mixture provides appropriate energy to channel the decomposition of the radical anion through the formation of the c-radical and the toluate anion.
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25. Ruling out H-abstraction from the solvent. These observations suggest that the radical intermediate might abstract a hydrogen atom either from the associated HMPA molecules or from the p-methyl substituent of another toluate subunit. Experiments to distinguish between these two pathways are currently being performed.