Molecules (Jul 2019)

Role of Pyridine Nitrogen in Palladium-Catalyzed Imine Hydrolysis: A Case Study of (E)-1-(3-bromothiophen-2-yl)-N-(4-methylpyridin-2-yl)methanimine

  • Gulraiz Ahmad,
  • Nasir Rasool,
  • Komal Rizwan,
  • Ataf Ali Altaf,
  • Umer Rashid,
  • Mohd Zobir Hussein,
  • Tariq Mahmood,
  • Khurshid Ayub

DOI
https://doi.org/10.3390/molecules24142609
Journal volume & issue
Vol. 24, no. 14
p. 2609

Abstract

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In the present study, 4-methylpyridin-2-amine was reacted with 3-bromothiophene-2-carbaldehyde and the Schiff base (E)-1-(3-bromothiophen-2-yl)-N-(4-methylpyridin-2-yl)methanimine was obtained in a 79% yield. Coupling of the Schiff base with aryl/het-aryl boronic acids under Suzuki coupling reaction conditions, using Pd(PPh3)4 as catalyst, yielded products with the hydrolysis of the imine linkages (5a−5k, 6a−6h) in good to moderate yields. To gain mechanistic insight into the transition metal-catalyzed hydrolysis of the compounds, density functional theory (DFT) calculations were performed. The theoretical calculations strongly supported the experiment and provided an insight into the transition metal-catalyzed hydrolysis of imines.

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