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The PtII isocyanide complex [Pt(ppy)Cl(CNC6H4-C≡C-Ph)] (1, Hppy=2-phenylpyridine) was co-crystallized with 1,4-diiodotetrafluorobenzene (1,4-DITFB), yielding 1·½(1,4-DITFB) adduct. The I···Cl halogen-bonding and π-π-stacking interactions combined with the rare π-hole(isocyano group)⋅⋅⋅dz2[PtII] interactions were identified via analysis of X-ray diffraction data of the co-crystals. These two types of structure-determining interactions supplemented each other, and the system of I⋯Cl and π-hole(isocyano group)⋅⋅⋅dz2[PtII] contacts achieved a 1D extended ladder-type architecture. The density functional theory calculations, employing a set of computational tools, verified the role of I⋯Cl and π-hole(isocyano group)⋅⋅⋅dz2[PtII] noncovalent bonds in the spectrum of noncovalent forces. The solid-state photophysical study revealed an amplification of luminescence intensity in the co-crystals, which is attributed to the suppression of the nonradiative relaxation pathways due to an increase in the rigidity of the chromophore center. [ABSTRACT FROM AUTHOR]

Reaction of [Ir(μ-Cl)(ppy)2]2 (1) with 4 equivs of CNC6H4X (X = F 2a, Cl 2b, Br 2c, I 2d) in the presence of 2 equivs of AgOTf in dichloromethane at 20–25 °C furnished the bisisocyanide complexes [Ir(ppy)2(CNC6H4X)2](OTf) ([3a–d](OTf); 72–87%). Reaction of [3a–d](OTf) with an excess of gaseous ammonia at room temperature gave the bisdiaminocarbene species [Ir(ppy)2{C(NH2)NHC6H4X}2](OTf) [5a–d](OTf) (73–83%); the two-step addition proceeds through an intermediate formation of appropriate monocarbene complexes [4a–d](OTf). Further reaction of [5a–d](OTf) with an excess of gaseous ammonia at 50 °C led to the cleavage of one diaminocarbene ligand to the cyanide ligand in [Ir(ppy)2(CN){C(NH2)NHC6H4X}] (6a–d) and this transformation is accompanied with the elimination of a substituted aniline. Treatment of [5a–d](OTf) with N(CH2CH2OH)3 at 50 °C resulted in the cleavage of the diaminocarbene ligand to the isocyanide and uncomplexed NH3; isocyanide remains bound to the iridium(iii) center in [Ir(ppy)2{C(NH2)NHC6H4X}(CNC6H4X)](OTf) (4a–d). All isolated compounds were characterized by elemental analyses (C, H, N), molar conductivity measurements, TG/DTA, HRESI+/−-MS, FTIR, 1D (1H, 13C{1H}, 19F{1H}) and 2D (1H,1H-COSY, 1H,13C-HMQC/1H,13C-HSQC, 1H,13C-HMBC) NMR, and also by X-ray diffraction (for the bisisocyanide 3, the diaminocarbene/isocyanide 4, the bisdiaminocarbene 5, and the diaminocarbene/cyanide 6 type complexes). [ABSTRACT FROM AUTHOR]

The reaction of bis(isocyanide)palladium complex cis-[PdCl2(CNXyl)2] (Xyl=2,6-Me2C6H3) with excess of 4,5-dichlorobenzene-1,2-amine in a C2H4Cl2/MeOH mixture affords monocationic bis(diaminocarbene) complex cis-[PdClC{(NHXyl)=NHC6H2Cl2NH2}{C(NHXyl)=NHC6H2Cl2NH2}]Cl (3) in moderate yield (42%). Complex 3 exists in the solid phase in the H-bonded dimeric associate of two single charged organometallic cations and two chloride anions according to X-ray diffraction data. The Hirshfeld surface analysis for the X-ray structure of 3 reveals that the crystal packing is determined primarily by intermolecular contacts H–Cl, H–H, and H–C. The intermolecular hydrogen bonds N–H···Cl and C–H···Cl in the H-bonded dimeric associate of 3 were studied by DFT calculations and topological analysis of the electron density distribution within the framework of QTAIM method, and estimated energies of these supramolecular contacts vary from 1.6 to 9.1 kcal/mol. Such non-covalent bonding means that complex 3 is an anionic receptor for the chloride anions. [ABSTRACT FROM AUTHOR]

Reaction of the palladium(II) and platinum(II) isocyanide complexes cis-[MCl2(CNR)2] [M = Pd, R = C6H3(2,6-Me2) (Xyl), 2-Cl-6-MeC6H3, cyclohexyl (Cy), t-Bu, C(Me)2CH2(Me)3 (1,1,3,3-tetramethylbuth-1-yl abbreviated as tmbu); M = Pt, R = Xyl, 2-Cl-6-MeC6H3, Cy, t-Bu, and tmbu] with N,N'-diphenylguanidine (DPG) leads to DPG-derived metal-bound deprotonated acyclic diaminocarbene (ADC) species. This reaction occurs via a two-step process, involving the initial coupling of the guanidine with one of the isocyanides and leading to deprotonated monocarbene monochelated species, while the next addition grants the deprotonated bis-carbene bis-chelated metal compounds. DPG behaves as nucleophile, deprotonating base, and chelator. The addition of DPG proceeded with different regioselectivity depending on the metal center and, in a larger extent, on the substituent R in RNCs. The X-ray diffraction studies for the deprotonated mono- and bis-carbene complexes confirmed the regioisomerism of these species and allowed the identification of ADC protolytic forms stabilized in the solid-state. 1D (1H and 13C{1H}) and 2D (1H,1H-NOESY; 1H,15N-HSQC; 1H,15N-HMBC) solution NMR of the obtained systems demonstrated their configuration isomerism accompanied by prototropic tautomerism. Together, the solid-state and solution data provide an insight into the flexible character of ADC species. [ABSTRACT FROM AUTHOR]

The dihalomethane-halide H2C(X)-X···X- (X = Cl, Br) halogen bonding was detected in a series of the cis-[PdX(CNCy){C(NHCy) NHC6H2Me2NH2}]X•CH2X2 (X = Cl, Br) associates by single-crystal XRD followed by DFT calculations. Although ESP calculations demonstrated that the σ-hole of dichloromethane is the smallest among all halomethane solvents (the maximum electrostatic potential is only 2.6 kcal/mol), the theoretical DFT calculations followed by Bader's QTAIM analysis (M06/DZP-DKH level of theory) confirmed the H2C(X)-X···X- halogen bond in both the solid-state and gas-phase optimized geometries. The estimated bonding energy in H2C(X)-X···X- is in the 1.9-2.8 kcal/mol range. [ABSTRACT FROM AUTHOR]

Syntheses and characterizations of novel phosphaheterocycles, 1-phenyl-4,4-dimethyl-1,4-dihydrophosphinoline (2a) and 1-phenyl-2-bromo-4,4-dimethyl-1,4-dihydrophosphinoline (2b), and their complexes with Pd(ii) and Pt(ii) are described. Reduction of 1-phenyl-4,4-dimethyl-1,4-dihydrophosphinoline 1-oxide (1a) and 1-phenyl-2-bromo-4,4-dimethyl-1,4-dihydrophosphinoline 1-oxide (1b) using trichlorosilane in refluxing benzene gave the target phosphines in a yield of 83–87%. Reactions of phosphines with acetonitrile complexes of Pd(ii) (3) and Pt(ii) (4) yielded bis(phosphine) species [MCl2L2] (5–8). Complexes 5–8 were characterized by 1H, 13C, 31P, 195Pt NMR and HRMS. The structures of all these new complexes were determined with single crystal X-ray diffraction. The configuration of the complexes in a CDCl3 solution was investigated via comparing of 31P NMR data in solution and solid state. [ABSTRACT FROM AUTHOR]

Reaction of organoiridium(III)-2-phenylpyridine complex, [Ir(ppy) 2 ( μ -Cl)] 2 (ppy = 2-phenylpyridinato- C 2 , N ), with 4-(2-bromophenyl)-1,2,3-thiodiazole (X) or 4-(2-bromophenyl)-1,2,3-selenadiazole (Y) in CH 2 Cl 2 yields to [Ir(ppy) 2 Cl(X)]·CH 2 Cl 2 ( 1 ) or [Ir(ppy) 2 Cl(Y)] ( 2 ), respectively. Both compounds were characterized by characterized by elemental analyses (C, H, N), HRESI + -MS, FTIR, and studied by single-crystal X-ray diffraction. The coordination environment of the central iridium(III) has a distorted octahedral geometry, four sites being occupied by two (ppy) − , which chelates in the C,N fashion, while the two other sites are filled with the Cl − and X (or Y) ligands. The intramolecular S ··· N and Se ··· Cl types of chalcogen bonds were found in the structures of 1 and 2 , respectively. Compound 1 is also present intramolecular pnicogen bonding and intermolecular halogen bonding (between CH 2 Cl 2 molecules) with the short N ··· Br (3.160 Å) and Cl ··· Cl (2.187 Å) distances. The crystal structures in 1 and 2 are stabilized by medium-strong intermolecular hydrogen bonding interactions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Dibromo-bis-isocyanide Pd complexes are prepared via metathetical reaction from chlorides. [•] Geometry of complexes in solution and solid-state is established on basis of spectroscopic data. [•] trans coordination modes are preferable for dibromo species in solution and in a solid state. [ABSTRACT FROM AUTHOR]

The reaction between the equimolar amounts of cis-[PdCl2(CNR¹)2] (R¹ = cyclohexyl (Cy) (1), tBu (2)) and the carbohydrazides R²CONHNH2 (R² = Ph (5), 4-ClC6H4 (6), 3-NO2C6H4 (7), 4-NO2C6H4 (8), 4-CH3C6H4 (9), 3,4-(MeO)2C6H3 (10), naphth-1-yl (11), fur-2-yl (12), 4-NO2C6H4CH2 (13), Cy (14), 1-(4-fluorophenyl)-5-oxopyrrolidin-3-yl (15), (pyrrolidin-1-yl)C(O) (16)) proceeds in refluxing CHCl3 for ca. 4 h. A subsequent workup provided the aminocarbene species cis-[PdCl2{C(NHNHC(O)R²)═N(H)R¹}(CNR¹)] (18-33) in good to excellent (80-95%) isolated yields. The coupling of equimolar amounts of cis-[PdCl2(CNR¹)2] (R¹ = Cy (1), tBu (2), 2,6-Me2C6H3 (Xyl) (3), 2-Cl-6-MeC6H3 (4)) and PhSO2NHNH2 (17) occurs similarly and affords the aminocarbenes cis-[PdCl2{C(NHNHS(O)2Ph)═N(H)R¹}(CNR¹)] (34-37; 60-90%). Complexes 18-37 were characterized by elemental analyses (C, H, N), ESI+-MS, IR, and 1D (¹H, 13C{¹H}) and 2D (¹H,¹H-COSY, ¹H,13C-HMQC/¹H,13C-HSQC, ¹H,13C-HMBC) NMR spectroscopy, as well as by X-ray diffraction for three species (34, 37, and 38). The catalytic properties of 18-37 in Suzuki-Miyaura cross-coupling in aqueous medium were evaluated, and 18-37 showed remarkable activity (0.001-0.01 mol % catalyst loading). The scope of the catalytic process covers sterically unhindered and sterically demanding aryl bromides and aryl iodides bearing donor and/or acceptor substituents and activated aryl chlorides. All organohalides reacted with a range of arylboronic acids at 80 °C within 2 h (100 °C and 3 h for the chlorides), providing target diaryls in yields up to 99% and with maximum TONs of 9.9 × 10³ (for aryl iodides), 4.7 × 104 (for aryl bromides), and 9.2 × 10³ (for aryl chlorides). [ABSTRACT FROM AUTHOR]

• A series of platinum(II) cyclometalated isocyanide complexes were prepared. • The X-ray diffraction data suggest the presence of (isocyano group)•••PtII interactions. • The isocyano nitrogen atom acts as a π-hole donor toward a d z 2-orbital of PtII atom. • Non-covalent interactions were studied by DFT calculations (NCI and QTAIM methods). • The CSD analysis verified more examples of (isocyano group)•••[ d9 -/ d8 -M] interactions. A series of platinum(II) isocyanide complexes [Pt(ppy)Cl(CNR)] (ppy = 2-phenylpyridinato-C2, N; R = Mes 1 , C 6 H 2 –2,6-Me 2 –4-Br 2 , C 6 H 2 –2-F-3-Cl-4-Br 3 , naphthalen-2-yl 4) were prepared and characterized by high resolution ESI-MS, 1D and 2D NMR, IR, UV–Vis absorption, and photoluminescence spectroscopies, as well as single-crystal X-ray diffraction. Analysis of X-ray diffraction data allowed us to identify (isocyano group)···PtII interactions where the nitrogen atom of the isocyano group acts as a π-hole donor toward a d z 2-orbital of PtII. The presence of these noncovalent interactions was confirmed by DFT calculations followed by NCI analysis and topological analysis of the electron density distribution within the framework of Bader's theory (QTAIM method). Processing of CSD data allowed verification of the contacts between coordinated isocyano moieties and various d9 and d8 - metal-centers (AuI, AuIII, AgI, PtII, PdII, NiII, RhI) to be performed. [Display omitted] [ABSTRACT FROM AUTHOR]