Enantioselective Protonation of Enol Esters with Bifunctional Phosphonium/Thiourea Catalysts

Eiji Yamamoto, Kodai Wakafuji, Yusuke Mori, Gaku Teshima, Yuki Hidani, Makoto Tokunaga

研究成果: ジャーナルへの寄稿記事

抄録

Bifunctional phosphonium/thioureas derived from tert-leucine behaved as highly selective catalysts for enantioselective protonation of enol esters, providing α-chiral ketones in yields of up to 99% with high enantioselectivities (up to 98.5:1.5 er). Control experiments clarified that a bulky tert-butyl group and phosphonium and thiourea moieties were necessary to achieve such high stereoselectivity. In addition, mechanistic investigations indicated the catalyst was converted to the corresponding betaine species, which served as a monomolecular catalyst.

元の言語英語
ページ(範囲)4030-4034
ページ数5
ジャーナルOrganic Letters
21
発行部数11
DOI
出版物ステータス出版済み - 6 7 2019

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Thiourea
Protonation
thioureas
esters
Esters
catalysts
Betaine
Catalysts
Ketones
Stereoselectivity
betaines
leucine
Enantioselectivity
ketones
Experiments
2-amino-3,3-dimethylbutanoic acid

All Science Journal Classification (ASJC) codes

  • Biochemistry
  • Physical and Theoretical Chemistry
  • Organic Chemistry

これを引用

Enantioselective Protonation of Enol Esters with Bifunctional Phosphonium/Thiourea Catalysts. / Yamamoto, Eiji; Wakafuji, Kodai; Mori, Yusuke; Teshima, Gaku; Hidani, Yuki; Tokunaga, Makoto.

:: Organic Letters, 巻 21, 番号 11, 07.06.2019, p. 4030-4034.

研究成果: ジャーナルへの寄稿記事

Yamamoto, Eiji ; Wakafuji, Kodai ; Mori, Yusuke ; Teshima, Gaku ; Hidani, Yuki ; Tokunaga, Makoto. / Enantioselective Protonation of Enol Esters with Bifunctional Phosphonium/Thiourea Catalysts. :: Organic Letters. 2019 ; 巻 21, 番号 11. pp. 4030-4034.
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