Palladium(II) catalyzed Suzuki C-C coupling reactions with imino- and amino-phosphine ligands


YILMAZ M. K., Ince S., Yilmaz S., KELEŞ M.

INORGANICA CHIMICA ACTA, vol.482, pp.252-258, 2018 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 482
  • Publication Date: 2018
  • Doi Number: 10.1016/j.ica.2018.06.013
  • Journal Name: INORGANICA CHIMICA ACTA
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.252-258
  • Çukurova University Affiliated: Yes

Abstract

A new series of bidentate PN type imino-(1-3) and amino-phosphine ligands (4-6) and their palladium(II) complexes [Pd(PN)Cl-2] (1a-6a) have been synthesized and fully characterized using spectroscopic and analytical methods, including P-31, H-1, C-13 NMR and FTIR spectroscopy and high resolution mass spectroscopy. The catalytic activities of the Pd( II) complexes were investigated for the Suzuki C-C coupling reactions of phenylboronic acid with aryl bromides using a substrate to catalyst ratio of 500/1. The effect of base, temperature and solvent has been investigated, and the highest reaction rates were observed at 80 degrees C in dimethylformamide (DMF) with K2CO3 as the base in 12 h. Under optimized reaction conditions, generally higher coupled product was obtained with substituted aryl bromides, including both electron-withdrawing (-formyl and -aceto) or -donating groups (-methyl and -methoxy) at -ortho or -para positions, except 2-bromoacetophenone which has bulkier -aceto group compared to the other aryl bromides.