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

Fenghai Guo; Matthew A McGilvary; Malcolm C Jeffries; Briana N Graves; Shekinah A Graham; Yuelin Wu

doi:10.3390/molecules22050723

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

Molecules. 2017 May 1;22(5):723. doi: 10.3390/molecules22050723.

Authors

Fenghai Guo¹, Matthew A McGilvary², Malcolm C Jeffries³, Briana N Graves⁴, Shekinah A Graham⁵, Yuelin Wu⁶

Affiliations

¹ Department of Chemistry, Winston-Salem State University, Winston Salem, NC 27110, USA. guof@wssu.edu.
² Department of Chemistry, Winston-Salem State University, Winston Salem, NC 27110, USA. mcgilvary336@gmail.com.
³ Department of Chemistry, Winston-Salem State University, Winston Salem, NC 27110, USA. mjeffries115@rams.wssu.edu.
⁴ Department of Chemistry, Winston-Salem State University, Winston Salem, NC 27110, USA. bgraves114@rams.wssu.edu.
⁵ Department of Chemistry, Winston-Salem State University, Winston Salem, NC 27110, USA. sgraham113@rams.wssu.edu.
⁶ School of Chemical and Environmental Engineering, Shanghai Institute of Technology, Shanghai 201418, China. wuyuelin517@hotmail.com.

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(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 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.

Keywords: 2,3-dihydropyridones; N-boc-4-pyridone; conjugate addition; rhodium (I)-complexes.

MeSH terms

Catalysis
Chlorides / analysis*
Chlorides / chemistry*
Coordination Complexes / chemistry*
Naphthalenes / chemistry
Pyridones / chemistry*
Rhodium / chemistry*
Stereoisomerism
Zinc Compounds / analysis*
Zinc Compounds / chemistry*

Substances

BINAP, 2-naphthol
Chlorides
Coordination Complexes
Naphthalenes
Pyridones
Zinc Compounds
4-pyridone
zinc chloride
Rhodium