Use of acetate as a leaving group in palladium-catalyzed nucleophilic substitution of benzylic esters

Tetrahedron Letters

Volumn 48, Issue 35, 2007, Pages 6109-6112

  Yokogi, Masashi ^a   Kuwano, Ryoichi ^a  

^a KYUSHU UNIVERSITY   (Japan)

Author keywords

Benzyl acetate; Homogeneous catalysis; Nucleophilic substitution; Palladium

Indexed keywords

ACETIC ACID; ACETIC ACID DERIVATIVE; ALCOHOL; AMINE; BENZENE DERIVATIVE; BENZYL ACETATE; ESTER DERIVATIVE; PALLADIUM; PHOSPHINE DERIVATIVE; SOLVENT;

ARTICLE; BENZYLATION; CATALYSIS; CATALYST; CHEMICAL REACTION; COMPLEX FORMATION;

EID: 34547466757     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.tetlet.2007.06.157     Document Type: Article

References (22)

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20. 4, and evaporated under reduced pressure. The residue was purified with a flash column chromatography on silica gel (EtOAc/hexane).
21. As with the reaction of benzylic carbonates (Ref. 4a), the reactivity of benzyl acetate 1a was lower than those of both electron-rich and -poor substrate. We speculated that the electron-donating group of 1 weakened the benzylic C-O bond. Meanwhile, the electron-withdrawing group may favor the pre-coordination of the palladium(0) on the aromatic ring of the benzylic ester.
22. 3-benzyl ligand on palladium. Triethylamine might be required for neutralizing the acetic acid liberated from benzyl acetate. The reaction conditions were insufficient for the reaction of 1a with malonates, resulting in no formation of 3.