Novel (oxazolinyl)phenyl phosphinite pincer ligand: Development of the first non-symmetrical, PCN type chiral palladium and platinum complexes

PCN‐ and PCS‐Pincer Palladium Complexes as Tandem Catalysts in Homoallylation Reactions

“…The use of isovanillin as the key building block, as pioneered by Nishiyama and co-workers (see complex D in Figure 1), [11] has allowed the regioselective introduction of oxazolinyl nitrogen donor and diphenylphosphinite phosphorus donor functionalities by chemoselective conversion of the two independent functional groups, i.e., the aldehyde and hydroxy groups. Here, we report on the development of a synthetic methodology to synthesize ECE'-pincer arene and aryl bromide ligands along with their corresponding palladium complexes starting from isovanillin as the general building block (Figure 2).…”

“…The filtrate was concentrated under reduced pressure and was fully dried in vacuum to give crude compound 10, which was used in the next step without further purification. 2-Bromo-3-formyl-6-methoxyphenyl Acetate (11) Compound 8 (1.16 g, 5 mmol) and Ac 2 O (0.47 mL, 5 mmol) were dissolved in pyridine (15 mL) and vigorously stirred at room temperature under N 2 for 1 h. Subsequently, pyridine was removed from the mixture under reduced pressure on a rotary evaporator. The resulting oily product was redissolved in demineralized water (20 mL) and the pH value of the mixture was then adjusted to 7 by adding saturated aqueous NaHCO 3 solution.…”

Facile synthesis of achiral and chiral PCN pincer palladium(II) complexes and their application in the Suzuki and copper-free Sonogashira cross-coupling reactions

“…Among them, 2e is a kind of chiral PCN pincer complex. To our knowledge, only Motoyama versions of PCN pincer palladium complexes with (oxazolinyl)phenyl phosphinite ligands via oxidative addition of an appropriate bromo-substituted derivative [32]. In connection with our own experience in the Pd-catalyzed reactions for the formation of C-C or C-N bonds [33][34][35][36][37], the obtained Pd compounds were applied to Suzuki and copper-free Sonogashira cross-coupling reactions.…”

Synthesis and structural characterization of enantiopure exo and endo six-membered oxazoline-derived palladacycles

“…Metal complexes of unsymmetrically substituted 2-oxazolines obtained from chiral amino acids and their derivatives have found a variety of applications, particularly in asymmetric synthesis [47]. Recently, a number of C * -chiral enantiopure exo [48][49][50], endo [48,[50][51][52][53][54][55][56][57][58][59][60][61][62] and pincer-type [58,[63][64][65][66][67][68][69][70] cyclopalladated oxazolines with a five-membered metalacycle have been reported (Chart 2). Other cyclopalladated oxazolines with planar and central chirality have also been studied [38,[71][72][73][74][75][76][77][78][79][80].…”