Palladium(II) allyl complexes with nitrogen–sulfur bidentate ligands. Substituent effects in the mechanism of allyl amination

Synthesis, stability and reactivity of palladium(0) olefin complexes bearing labile or hemi-labile ancillary ligands and electron-poor olefins

“…The ensuing K exc span a very narrow interval (2.5 6 K exc 6 7.1) and these determinations demonstrate (i) the scarce influence of the olefin on the coordinating capability of different ligands and (ii) the very similar coordinating ability between the labile ligands N-N or N-S (the latter observation is in accord with former determinations of the ligands exchange equilibria in the case of Pd(II) allyl complexes [66,67]). .…”

Softening the Donor-Set: From [Cu(P^P)(N^N)][PF6] to [Cu(P^P)(N^S)][PF6]

“…For an initial investigation, we chose the NˆS ligands iPrSPy and tBuSPy shown in Scheme 1. They were prepared by following literature procedures and the 1 H and 13 C{ 1 H} NMR spectra (Figures S1 and S2) were in agreement with those reported [25,26] (Figure S3), the phenyl ring with C40 was disordered and was modelled over two sites with 65% and 35% occupancies. A disorder involving the iPrSPy ligand was modelled over two equal-occupancy sites; the S atom was common to both ligand positions.…”

“…[Cu(MeCN) 4 ][PF 6 ] was prepared by the published method [33]. The NˆS ligands were prepared according to the literature and the NMR spectroscopic data matched with those reported [25,26]. 134.7 (C C3 ), 134.5/132.9/129.3 (C D'2,3,4 ), 132.9 (C C5 ), 132.7 (C D2 ), 131.2 (C D'1 ), 130.7 (C D4 ), 130.0/125.7 (C C6+C4 ), 129.5 (C D3 ), 125.5 (C D1 ), 125.1 (C A3 ), 124.6 (C A5 ), 120.8 (C C2 ), 38.6 (C a+Pr-CH ), 21.9 (C Pr-Me ).…”

Supported palladium catalysis using a heteroleptic 2-methylthiomethylpyridine–N,S–donor motif for Mizoroki–Heck and Suzuki–Miyaura coupling, including continuous organic monolith in capillary microscale flow-through mode

“…To achieve this, functionalisation of the 4-position of the pyridine ring with a phenolic group was considered desirable in order to minimise any steric interaction between the phenolic group and the metal centre. The synthesis in Scheme 1 was developed based on the reaction of commercially available 1 with acetyl bromide to give 2 with slight modification of a reported method 8 (glacial acetic acid as solvent rather than neat reagents) to increase the yield from 31 to 91%; employing the protocol of van den Heuvel et al (trifluoroacetic anhydride to generate 4-bromo-2-trifluoroacetoxymethylpyridine, followed by hydrolysis with NaOH) 9a for synthesis of the 5-bromo analogue to obtain known compound 9b 3 (62%); bromination of 3 to give 4 (87%), a modification of the protocol of Canovese et al (reaction with thiomethoxide) 10 for the synthesis of related compounds to give 5 (72%); and Suzuki-Miyaura chemistry to give 6 (90%; overall yield 32%). Compound 7 was synthesised as a model for the benzyl ether connectivity between ligand and the polymer backbone (overall yield 30%), and palladium(II) complexes of 6 and 7, PdCl 2 (L 1 ) (8) and PdCl 2 (L 2 ) (9), respectively, were obtained on reaction with PdCl 2 (NCMe) 2 under reaction conditions identical to those used to add palladium(II) to polymers functionalised with compound 6.…”