Controlled dealkylation by BBr3: Efficient synthesis of para-alkoxy-phenols

Tetrahedron Letters

Volumn 53, Issue 46, 2012, Pages 6191-6194

  Pasquini, Chiara ^a   Coniglio, Alessandra ^a   Bassetti, Mauro ^a  

^a SAPIENZA UNIVERSITY OF ROME   (Italy)

Author keywords

Cleavage reactions; Hydroquinone; Iodoarenes; Phenols; Synthetic methods

Indexed keywords

BORON TRIBROMIDE; HYDROQUINONE DERIVATIVE; OXYGEN; PHENOL DERIVATIVE;

ARTICLE; CHEMICAL ANALYSIS; CHEMICAL REACTION; CHEMICAL STRUCTURE; DEALKYLATION; STOICHIOMETRY; SYNTHESIS;

EID: 84867579521     PISSN: 00404039     EISSN: 18733581     Source Type: Journal    
DOI: 10.1016/j.tetlet.2012.08.132     Document Type: Article

References (31)

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29. Under electrophilic conditions the iodo moiety can be lost because of protodeiodination reactions, resulting in transhalogenation or dehalogenation side processes Waldvogel, S. R. Sci. Syn., Knowledge Updates 2010, 1, 487-498. However, we did not observe the formation of products other than the monodealkylated and the fully dealkylated hydroquinone. 18. Dealkylation yields are given as percentages of conversion of 1.
30. Higher stabilization offered to the ylide adduct (Scheme 2) by -OR (electrondonor) in the first cleavage event, with respect to -OBBr2 (electronwithdrawing), in the second cleavage event, might explain this evidence.
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