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The reaction of the bis(dichlorogold) complex of 2,3-bis(diphenylphosphino)maleic anhydride (L1) with S(SiMe3)2 in the presence of NaBPh4 yields the ionic dodecanuclear cluster compound [Au12(PPh2)2S4(L2)4](BPh4)2 (1). During the formation of 1, the initial ligand L1 is transformed into the doubly sylilated derivative, 3,4-bis(diphenylphosphino)-2,5-bis(trimethylsilyloxy)-furan (L2). The presence of bridging PPh2 groups is a result of the transformation of L1 in the coordination sphere of Au(i). Compound 1 was characterized by single crystal X-ray diffraction and electrospray-ionization (ESI) mass spectrometry. [ABSTRACT FROM AUTHOR]

The octaferrocenyl cluster [Ag8(SeCH2Fc)8(PPh3)4] 3can be prepared in good yield from FcCH2SeSiMe31and solubilized AgOAc. The reagent 1and disubstituted 1,1′-fc(CH2SeSiMe3)22are themselves prepared in good yield from Li[SeSiMe3] with FcCH2Cl and fc(CH2Cl)2, respectively. Reaction of 2with [Zn(OAc)2(tmeda)] yields the dimeric complex [{Zn(fc(CH2Se)2)(tmeda)}2] 4. The structures of 3, 4and di(ferrocenylmethyl)diselenide 5, as determined by single crystal X-ray crystallography, are reported. [ABSTRACT FROM AUTHOR]

Three novel selenophenolato hydrido iron(II) complexes [ cis -(H)(SeAr)Fe(PMe 3 ) 4 ] ( 4–6 ) (Ar=C 6 H 5 ( 4 ), p -MeOC 6 H 4 ( 5 ) and o -MeC 6 H 4 ( 6 )) were prepared through the reaction of Fe(PMe 3 ) 4 with selenophenols ArSeH ( 1–3 ) via Se–H activation. The iron hydrido complexes 4 , 5 and 6 could catalyze the hydrosilylation of aldehydes and ketones. Among them complex 5 is the best catalyst for this process. Furthermore, α,β-unsaturated alcohols could be obtained from the selective reduction reactions of the corresponding α,β-unsaturated carbonyls catalyzed by hydrido iron(II) complex 5 . This catalytic system has good tolerance for some common groups but it is easy to reduce the nitro group to an amino group. The experiments indicate that the chemoselectivity for this catalytic system is CHO> NO 2 > C( O)CH 3 . The crystal structure of 6 was determined by X-ray diffraction. [ABSTRACT FROM AUTHOR]

The C(carbene)N(amino)N(amine)-pincer nickel(II) bromides 1a-c were hydrogenated to the corresponding nickel(II) hydrides 2a-c by (EtO)3SiH/NaOtBu or NaBH4. These nickel(II) hydrides 2a-c were characterized by NMR and IR spectroscopy as well as X-ray diffraction. The catalytic performance of complex 2b for hydrodehalogenation reactions was explored. With a combination of 3 mol % catalyst loading, (EtO)3SiH/NaOtBu/toluene/80 °C and different reaction times, organic halides were successfully reduced to the related alkanes. A catalytic radical mechanism is proposed and partially verified by experiments. [ABSTRACT FROM AUTHOR]

The hydrosilylation of aldehydes and ketones under mild conditions with hydrido thiophenolato iron(II) complexes [ cis –Fe(H)(SAr)(PMe 3 ) 4 ] ( 1–4 ) as catalysts is reported using (EtO) 3 SiH as an efficient reducing agent in the yields up to 95%. Among them complex 1 is the best catalyst. Complex 1 could also be used as catalyst to reduce the α,β-unsaturated carbonyl compounds selectively to the α,β-unsaturated alcohols in high yields. [ABSTRACT FROM AUTHOR]

In this paper the reactions of iron(II) hydrides 6 – 10 formed by selective C F/C H bond activation in fluoroaryl-imines were reported. Iron hydrides 6 and 7 reacted with haloalkane to give rise to the corresponding iron halides 11 and 12 with the mer -rearrangement of the three trimethylphosphine ligands. The related trifluoromethylcarboxyl iron complexes 13 and 14 with the carboxyl group as monodentate ligand were obtained from the reactions of hydrides 8 and 9 with F 3 CCOOH. The reaction of iron hydride 6 with Lewis acid LiBF 4 delivered ionic iron complex 15 . Both the reaction of iron hydride 10 with Me 3 SiC C H and the reaction of iron bromide 11 with Me 3 SiC CLi could provide the derivative trimethylsilylacetylenyl iron(II) complexes 16 and 17 respectively. The molecular structures of complexes 12 , 13 and 17 were determined by single crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

Three novel unsymmetrical η³-2-azaallyl cobalt(I) complexes, [(2-PPh2)C6H4]CH N[CHC6H4(4-R)]Co(PMe3)2 (4-6) (R = H (4); Cl (5); and OMe (6)), were synthesized by the reactions of Schiff base ligands [(2-PPh2)C6H4]CH N[CH2C6H4(4-R)] (1-3) (R = H (1); Cl (2); and OMe (3)) with CoMe(PMe3)4 via sp³ C-H bond activation under mild reaction conditions. Complex {[(2-PPh2)C6H4]CH NCH3[CHC6H4(4-R)]Co(PMe3)2}I (7) as an 18e cobalt(III) salt was obtained through the reaction of 4 with iodomethane. The substitution reaction of complex 4 with carbon monoxide afforded the dicarbonyl cobalt(I) complex [(2-PPh2)C6H4]CH[N CHC6H4(4-R)]Co(CO)2(PMe3) (8). The molecular structures of complexes 4-8 were determined by single crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

The preligand pyridine-2-amino(methyl)-dimethylsilane ( 1 ) was used to synthesize silyl iron hydride. Iron(II) hydride FeH(N( κ N-C 5 H 4 N)Me(SiMe 2 ))(PMe 3 ) 3 ( 2 ) was obtained through the reaction of 1 and Fe(PMe 3 ) 4 via the activation of one Si H bond and the coordination of nitrogen atom of pyridine. The substitution reaction of complex 2 with haloalkane (CH 3 I and EtBr) delivered complexes FeX(N( κN -C 5 H 4 N)Me(SiMe 2 ))(PMe 3 ) 3 (X = I ( 3 ); Br ( 4 )). Complex 2 reacting with acetylacetone resulted in the formation of Fe(acac)(N( κN -C 5 H 4 N)Me(SiMe 2 ))(PMe 3 ) 3 ( 5 ). However, the insertion products Fe(η 3 -OCOH)(N( κ N-C 5 H 4 N)Me(SiMe 2 ))(PMe 3 ) 3 ( 6 ) and Fe(η 3 -Ph-NCOH)(N( κN -C 5 H 4 N)Me(SiMe 2 ))(PMe 3 ) 3 ( 7 ) were formed through the insertion of the unsaturated bonds into Fe H bond. Complex 6 could also be synthesized through the substitution reaction of 2 with HCOOH. The molecular structures of complexes 2 and 4 – 7 were determined by single crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

• Synthesis and characterization of two novel Pd(II)-Na Schiff base complexes. • Evaluation of cytotoxicity of both complexes towards MCF-7 human breast cancer. • Assessment of in vitro antibacterial activity of both synthesized compounds. • Characterization of nanoscaled products of both complexes upon pyrolysis. Novel bi- and trinuclear palladium(II)-sodium complexes, {[P d L]Na(NO 3)(EtOH)} (1) and {[P d L] 2 Na}Cl (2) based on salophen-type Schiff base N,N'-(1,2-phenylene)-bis(3-methoxysalicylideneimine) (H 2 L) were synthesized under ambient and sonochemical conditions. Ultrasonication proved to be a more effective method for the rapid synthesis of these bi- and trinuclear complexes under mild conditions. On the basis of the molecular structure of complexes 1 and 2 , each palladium atom is placed in the "inner" N 2 O 2 compartment, and the sodium atoms are located in the "outer" O 2 O' 2 compartment of the twofold deprotonated bis -Schiff base ligand. In both complexes, each Pd(II) ion is four coordinated showing square planar geometry, whereas the Na(I) ions in complexes 1 and 2 adopt two different geometries, namely hepta and octa coordination, respectively. In addition, the solventless thermolysis of both complexes at 500 °C was also studied by thermal gravimetric analysis (TGA). EDX and powder XRD data pointed out the presence of highly pure nanoscaled materials. Furthermore, the anticancer and antibacterial activities of bi- and trinuclear complexes were examined towards MCF-7 human breast cancer cell line and evaluated against one gram-negative strain (Escherichia coli ATCC 25922) and one gram-positive strain (Staphylococcus aureus ATCC 6538). The in vitro studies revealed that complex 2 exhibited higher anticancer activity against MCF-7 cell line as well as better antibacterial effect on the examined bacteria strains than complex 1. [Display omitted] [ABSTRACT FROM AUTHOR]

A new amine functionalized double chelate NHC nickel complex 2 was synthesized and characterized. Complexes 4a and 4b were generated through an improved synthetic method. Catalytic ability of the three nickel complexes were tested in Kumada coupling reaction. Complex 2 showed the best catalytic activity among them. With only 0.5 mol% of complex 2 , the coupling of aryl chlorides with Grignard reagents received good yields. [ABSTRACT FROM AUTHOR]

The reductive dehydration of amides to nitriles under hydrosilation conditions with hydrido thiophenolato iron(II) complexes [ cis -Fe(H)(SAr)(PMe 3 ) 4 ] ( 1 – 4 ) as catalysts is reported using (EtO) 3 SiH as an efficient reducing agent in the yields up to 93%. The merits of this catalytic system, the low catalyst loadings (2 mol%) and the amount of efficient reducing agent (EtO) 3 SiH, make this method more attractive. [ABSTRACT FROM AUTHOR]

The bifunctional Iigand estechol-4,5 dithiol, H2Dtcat, has been synthesized, and the structure of the bin Br adduct, (HS)2C6H2(OH)2·2Ph4Br·H2O, has been determined. The syntheses, molecular structures, electronic structures, and magnetic properties of the monoanionic [(Dtcat2-)2M], (M = Ni, V and M o Cu, VI) complexes have been obtained as Ph4PBr double salts, [M(S2C6H2(OH)2)2][Ph4P]3Br2. These and the antiferromagnetically coupled dimetic [(Dtcal)2 Fe][Ph4P]2·4DMF domplex, VII, have been structurally chaiacterized. The centrosymmetric (M(S2C6H2(OH)f complexes in the X-ray isomorphous V and Vi are connected via H-bonding to Br ions to form one-dimensional chains well separated from each other by the Ph4P+ cations. Magnetic measurements show V to be a S o ½ and VI a S = O molecules. The distribution of electrons in these compounds have been determined by density functional theory calculations which show V to be a radical anion Ni(ll) complex and Via partially otddiced-Iigand, reduced-copper complex. The 4,5 dithio-oquinorle [(Dtoq)2Ni][Ph4P]2 and [(Dtoq)2Cu][Ph4P]2 orthoquinone derivatives of V and VI have been obtained by oxidaton, and their molecular structures have been determined. The dimetic ([FeS2C6H2(OH)2)2)2- complex, (VII) also cystallizes in chains where all OH groups partidpate in extensive H-bonding. The structure of the dianion VII contains S-coordinated Fe(Ill) tais in a square pyramidal coordination. In VII, two low spin Fe(III) (S = ½) sites are weakly coupled antitenomagneticalty with a μeff of 2.81BM at 270 K and 0.91 BM at 10 K. [ABSTRACT FROM AUTHOR]