Sequential Michael Addition/Electrophilic Alkynylation: Synthesis of alpha-Alkynyl-beta-Substituted Ketones and Chromanones

Autor(es)

Teodoro, Bruno V. M. ^[1] ; Silva, Jr., Luiz F. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Quim, Dept Quim Fundamental, BR-05508000 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Organic Chemistry; v. 83, n. 21, p. 13604-13611, NOV 2 2018.
• Citações Web of Science: 1

Resumo

We describe the synthesis of alpha-alkynyl-beta-substituted cyclic ketones and analogue chromanones via one-pot Michael addition/hypervalent iodine-based alpha-alkynylation. Cu(I)-catalyzed Michael addition using either alkyl-aluminum or Grignard reagents, followed by diastereoselective electrophilic alkynylation of the resulting enolate by 1-ethynyl-1 lambda(3),2-benziodoxol-3(1H)-one (EBX) resulted in the alpha-alkynyl-beta-substituted cyclic ketones or chromanones within 34-89% yield (16 examples). The reaction was successfully upscaled to the 5 mmol scale, and further functionalization of a model alkynylated ketone was demonstrated. (AU)

• Processo FAPESP: 15/00527-4 - Iodo hipervalente: metodologia e síntese total
• Beneficiário: Luiz Fernando da Silva Júnior
• Modalidade de apoio: Auxílio à Pesquisa - Regular