Gold(I) complexes of sterically demanding phosphines derived from 2,6-dibenzhydryl-4-methylphenyl core viz: 2,6-dibenzhydryl-N,N-bis((diphenylphosphane)-methyl)-4-methylaniline (1), (2,6-dibenzhydryl-4-methylphenyl)-diphenylphosphane (2), N-(2,6-dibenzhydryl-4-methylphenyl)-1,1-diphenylphosphanamine (3), and (2,6-dibenzhydryl-4-methylphenoxy)diphenylphosphane (4) are described. The reaction of 1 with 2 equiv of [AuCl(SMe 2 )] in dichloromethane yielded [{AuCl} 2 {Ar*N(CH 2 PPh 2 ) 2 }] (5), which on further treatment with 2 equiv of AgSbF 6 and 1 equiv ofEquimolar reactions of bulky phosphines 2, 3, and 4 with [AuCl(SMe 2 )] resulted in [AuCl(PPh 2 Ar*)] (8), [AuCl(PPh 2 NHAr*)] (9), and [AuCl(PPh 2 OAr*)] (10). Complexes 9 and 10 on treatment with AgSbF 6 in CH 3 CN produced the cationic complexes [Au(NCCH 3 )(PPh 2 NHAr*)][(SbF 6 )] (11) and [Au(NCCH 3 )(PPh 2 OAr*)][(SbF 6 )] ( 12), respectively. The molecular structure of complex 6 revealed the presence of a strong intramolecular aurophilic interaction with a Au•••Au distance of 2.9720(4) Å. Careful analysis of molecular structure of 5 revealed the presence of rare Au•••H−C (sp 3 ) interactions between the gold(I) atom and one of the methylene protons of −NCH 2 PPh 2 groups. The solution 1 H NMR signals of the methylene protons of 5 showed a considerable downfield shift (∼1 ppm) compared to that of the free ligand indicating their interactions (Au•••H) with the Au atom. Complexes 8 and 10 also showed Au•••H interactions in their molecular structures. The existence of the Au•••H interaction was studied by variable temperature 1 H NMR data in the case of complex 5 and further evinced by the QTAIM analysis in complexes 5, 8, and 10.

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In this article, the synthesis, structural studies, and luminescence properties of Cu I , Ag I , and Au I complexes of pyrimidine-based phosphine [C 4 H 3 N 2 -2-NH(CH 2 PPh 2 )] ( 1 ) are described. The reactions of 1 with CuX led to the isolation of one-dimensional (1D) chain, tetranuclear ladder, or cyclic derivatives. The structural features of these complexes are greatly influenced by the metal-to-ligand ratio, reaction conditions, and CuX (X = Cl, Br or I) employed. In the case of CuCl and CuBr, one-dimensional coordination polymers [{CuCl}{C 4 H 3 N 2 -2-NH(CH 2 PPh 2 )}] ∞ ( 2 ) and [{CuBr}{C 4 H 3 N 2 -2-NH(CH 2 PPh 2 )}] ∞ ( 3 ) were obtained, whereas CuI afforded tetracopper complex [{CuI} 4 {C 4 H 3 N 2 -2-NH(CH 2 PPh 2 )} 2 (NCCH 3 ) 2 ] ( 4 ) having Cu 4 ladder structure supported by P∩N-bridging coordination of 1 . The reaction of 1 with AgOTf yielded unprecedented one-dimensional chain structure [{AgOTf}{C 4 H 3 N 2 -2-NH(CH 2 PPh 2 )}] ∞ ( 5 ), whereas the reaction with AgBF 4 produced a 12-membered dinuclear complex, [{Ag}{C 4 H 3 N 2 -2-NH(CH 2 PPh 2 )}] 2 [BF 4 ] 2 ( 6 ), with each silver atom having a linear geometry. Gold complex [{AuCl}{C 4 H 3 N 2 -2-NH(CH 2 PPh 2 )}] 2 ( 7 ) was synthesized by reacting 1 with [AuCl(SMe 2 )]. Compounds 2 – 4 were also prepared using a pestle and mortar by grinding method in almost quantitative yield. Complex 4 with a Cu···Cu distance of 2.828(5) Å shows high luminescence due to the nonbonded metal···metal interactions.

The grafting of an aminobis(phosphine)–PdII complex (PNP–PdII) [PdCl2{(Ph2P)2N(CH2)3Si(OMe)3}] (2) on graphene oxide (GO) has been carried out by a condensation reaction between methoxysilane groups of 2 and hydroxyl groups of GO. The composite material was characterized by FTIR spectroscopy , solid‐state 31P NMR spectroscopy, SEM, TEM, XPS and ICP‐AES techniques. All these tools support the clean immobilization of compound 2 on GO. The composite material showed high catalytic activity in Suzuki–Miyaura, Ullmann coupling and cyanation reactions. The heterogeneity of the composite was confirmed by a hot filtration test. The immobilized PNP–PdII shows comparable activity to its homogeneous analogue 2. The recycling ability of the catalyst was examined for five consecutive runs, which showed little or no reduction in its catalytic efficiency.

The synthesis and structural studies of palladium(II) complexes of sterically demanding mono‐phosphine Ar*PPh2 (1) (Ar*=2,6‐dibenzhydryl‐4‐methylphenyl) are described. The reactions of 1 with [Pd(COD)Cl2] and [Pd(η3‐C3H5)Cl]2 in 2 : 1 molar ratios afforded mononuclear complexes trans‐[PdCl2{(PPh2Ar*)‐κ1‐P}2] (2) and [Pd(η3‐C3H5)Cl{(PPh2Ar*)‐κ1‐P}] (3), respectively. Both the complexes have been fully characterized through NMR spectroscopy, elemental analyses, and single‐crystal X‐ray analysis. The molecular structures of 2 and 3 showed C−H⋅⋅⋅π interactions between methine hydrogen of one of the Ph2CH groups with the centroid of one of the phenyl rings of the PPh2 group. Complex 2 also showed intramolecular π⋅⋅⋅π stacking interactions between the phenyl rings of Ph2CH and PPh2 groups. In addition, complex 2 also showed C−H⋅⋅⋅Pd anagostic interaction between the methine hydrogen of one of the Ph2CH groups and the palladium center. The palladium complex 2 is found to be an efficient catalyst for the direct C‐5 arylation of imidazole derivatives under aerobic conditions.

This paper describes the synthesis of resorcin[4]arene based octaphosphinite ligands and their tetra-pincer NiII and PdII complexes and rhodium-octaphosphinite catalyzed hydroformylation of styrene and its derivatives.

This manuscript describes the syntheses of pyridine appended triazole-based mono- and bisphosphines, [o-Ph2P(C6H4){1,2,3-N3C(Py)C(H)}] (2), [o-Br(C6H4){1,2,3-N3C(Py)C(PPh2)}] (3), [C6H5{1,2,3-N3C(Py)C(PPh2)}] (4), Ph2P(C6H4){1,2,3-N3C(Py)C(PPh2)}] (5) and [3-Ph2P-2-{1,2,3-N3C(Ph)C(PPh2)}C5H3N] (6), their palladium, platinum chemistry and catalytic applications....

A mononuclear complex, [LCo(L′)2]ClO4⋅MeOH⋅H2O (1) (L′=4‐aminopyridine) and a binuclear heterometallic complex, [LCo(L′′)2Na(ClO4)2]⋅0.5H2O (2) (L′′=1‐methylimidazole) have been prepared from a Schiff‐base ligand (H2L=N, N′‐bis(3‐methoxysalicylidehydene)cyclohexane‐1,2‐diamine). The formation of both complexes were confirmed by employing several analytical techniques including single crystal X‐ray diffraction. The molecular structure of 1 consists of a [LCo(L′)2]+ cation associated with a [ClO4]− ion. Complex 2 contains a Co(III) ion and a Na(I) ion and thus it results a heterometallic Co(III)‐Na(I) compound. The Co(III) ion is in a distorted octahedral geometry in both complexes. Phenoxazinone synthase activity of 1 and 2 have been investigated. The oxidation of 2‐aminophenol (OAPH) to 2‐aminophenoxazine‐3‐one (APX) follows saturation rate kinetics with the formation of a catalyst‐substrate adduct. Mass analysis and electrochemical properties of both complexes have been investigated and they are in full support of the saturation rate kinetics.