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Rhodium(I)-Complexes Catalyzed 1,4-Conjugate Addition of Arylzinc Chlorides to N-Boc-4-pyridone.

ABSTRACT: Rhodium(I)-complexes catalyzed the 1,4-conjugate addition of arylzinc chlorides to N-Boc-4-pyridone in the presence of chlorotrimethylsilane (TMSCl). A combination of [RhCl(C?H?)?]? and BINAP was determined to be the most effective catalyst to promote the 1,4-conjugate addition reactions of arylzinc chlorides to N-Boc-4-pyridone. A broad scope of arylzinc reagents with both electron-withdrawing and electron-donating substituents on the aromatic ring successfully underwent 1,4-conjugate addition to N-Boc-4-pyridone to afford versatile 1,4-adducts 2-substituted-2,3-dihydropyridones in good to excellent yields (up to 91%) and excellent ee (up to 96%) when (S)-BINAP was used as chiral ligand.

SUBMITTER: Guo F

PROVIDER: S-EPMC6154701 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Rhodium(I)-Complexes Catalyzed 1,4-Conjugate Addition of Arylzinc Chlorides to N-Boc-4-pyridone.

Guo Fenghai F McGilvary Matthew A MA Jeffries Malcolm C MC Graves Briana N BN Graham Shekinah A SA Wu Yuelin Y

Molecules (Basel, Switzerland) 20170501 5

Rhodium(I)-complexes catalyzed the 1,4-conjugate addition of arylzinc chlorides to <i>N</i>-Boc-4-pyridone in the presence of chlorotrimethylsilane (TMSCl). A combination of [RhCl(C₂H₄)₂]₂ and BINAP was determined to be the most effective catalyst to promote the 1,4-conjugate addition reactions of arylzinc chlorides to <i>N</i>-Boc-4-pyridone. A broad scope of arylzinc reagents with both electron-withdrawing and electron-donating substituents on the aromatic ring successfully underwent 1,4-conju ...[more]

PMID: 28468302

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