Regioselective Access to Sultam Motifs through Cobalt-Catalyzed Annulation of Aryl Sulfonamides and Alkynes using an 8-Aminoquinoline Directing Group

The use of cobalt as catalyst in direct C[BOND]H activation protocols as a replacement for more expensive second row transition metals is currently attracting significant attention. Herein we disclose a facile cobalt-catalyzed C[BOND]H functionalization route towards sultam motifs through annulation of easily prepared aryl sulfonamides and alkynes using 8-aminoquinoline as a directing group. The reaction shows broad substrate scope with products obtained in a highly regioselective manner in good to excellent isolated yields. Mechanistic insights suggest the formation of a Co(III)-aryl key species via a rate-determining arene C[BOND]H activation during the annulation reaction

Consumer Multicultural Identity Affiliation: Reassessing Identity Segmentation in Multicultural Markets

The increasing intra-national diversity of many modern markets poses challenges to identity segmentation. As consumers require greater recognition of their diverse identities from brands, marketing science and practice are in search of theories and models that recognize and capture identity dynamics as impacted by cultural influences both from beyond and within national market borders. This paper extends consumer acculturation theory into multicultural market realities and offers a Consumer Multicultural Identity Affiliation (CMIA) Framework5 that distinguishes and integrates three key types of intra- and trans-national cultural influences informing identity dynamics. By examining consumer cultural identities within the CMIA framework in a mixed-method, two-country study, we show that gaining such an integrative view on cultural identity affiliations uncovers greater diversity and complexity (mono-, bi-, or multi-cultural) of consumer segments. We conclude with discussing future directions for CMIA applications to support marketing managers, scholars and educators dealing with culturally heterogeneous markets

The emerging role of MIR-146A in the control of hematopoiesis, immune function and cancer

MicroRNA (miRs) represent a class of small non-coding regulatory RNAs playing a major role in the control of gene expression by repressing protein synthesis at the post-transcriptional level. Studies carried out during the last years have shown that some miRNAs plays a key role in the control of normal and malignant hgematopoiesis. In this review we focus on recent progress in analyzing the functional role of miR-146a in the control of normal and malignant hematopoiesis. On the other hand, this miRNA has shown to impact in the control of innate immune responses. Finally, many recent studies indicate a deregulation of miR-146 in many solid tumors and gene knockout studies indicate a role for this miRNA as a tumor suppressor

Large bite bisphosphite, 2,6-C5H3N{CH2OP(–OC10H6)(μ-S)(C10H6O–)}2: synthesis, derivatization, transition metal chemistry and application towards hydrogenation of olefins

Large bite bisphosphite ligand, 2,6-C5H3N{CH2OP(–OC10H6)(μ-S)(C10H6O–)}2 (2), is obtained by reacting chlorophosphite, {-OC10H6(μ-S)C10H6O-}PCl (1) with 2,6-pyridinedimethanol in presence of triethylamine.Treatment of 2 with aqueous solution of H2O2 or elemental sulfur resulted in the formation of bis(oxide) or bis(sulfide) derivatives, 2,6-C5H3N{CH2OP(E)(–OC10H6)(μ-S)(C10H6O–)}2 (3, E = O; 4, E = S) in quantitative yield.The 10-membered cationic chelate complex, [RuCl(η6-C10H14)η2-2,6-C5H3N{CH2OP(–OC10H6)(μ-S)(C10H6O–)}2-κP,κP]Cl (5) is produced in the reaction between [Ru(p-cymene)(μ-Cl)(Cl)]2 and bisphosphite 2, whereas the neutral chelate complex, cis-[Rh(CO)Cl{2,6-C5H3N{CH2OP(–OC10H6(μ-S)C10H6O–)}2}-κP,κP] (6) is isolated in the reaction of 2 with 0.5 equiv.of [Rh(CO)2Cl]2.Compound 2 on treatment with M(COD)Cl2 (M = Pd, Pt) produce the chelate complexes, [MCl2{η2-2,6-C5H3N{CH2OP(–OC10H6)(μ-S)(C10H6O–)}2}-κP,κP] (7, M = Pd;10, M = Pt).Similarly the reaction of bisphosphite 2 with Pd(COD)MeCl affords cis-[PdMe(Cl)η2-2,6-C5H3N{CH2OP(–OC10H6)(μ-S)(C10H6O–)}2-κP,κP] (8).Treatment of 2 with [Pd(η3- C3H5)Cl]2 in the presence of AgClO4 furnish the cationic complex, [Pd(η3-C3H5)η2-2,6-C5H3N{CH2OP(–OC10H6)(μ-S)(C10H6O–)}2-κP,κP]ClO4 (9). The binuclear complex, [Au2Cl2{2,6-C5H3N{CH2OP(–OC10H6)(μ-S)(C10H6O–)}2}-κP,κP] (11) is obtained in the reaction of compound 2 with two equiv. of AuCl(SMe2), where the ligand exhibits bridged bidentate mode of coordination. All the complexes are characterized by the 1H NMR, 31P NMR, elemental analysis and mass spectroscopy data. The cationic ruthenium complex 5 is proved to be an active catalyst for the hydrogenation of styrene and α-methyl styrene.© Elsevie

Derivatisation and transition metal chemistry of a new monophosphinite ligand: 2-(diphenylphosphinoxy)naphthyl

Reaction of monophosphinite ligand, 2-(diphenylphosphinoxy)naphthyl, C10H7OPPh2 (1) with elemental sulphur or selenium gives the corresponding sulphide C10H7OP(S)Ph-2 (2) or selenide C10H7OP(Se)Ph-2 (3) derivatives. Reaction of 1 with [CpRu(PPh3)(2)Cl] gives monosubstituted complex, [CpRu(C10H7OPPh2)(PPh3)Cl] (4) as well as the disubstituted complex, [CpRu(C10H7OPPh2)(2)Cl] (5) depending upon the reaction conditions. Treatment of 1 with [Rh(CO)(2)Cl](2) affords a trans-complex, [Rh(CO)(C10H7OPPh1)(2)Cl] (6). Reaction of 1 with [Pd(COD)Cl-2] results in the formation of an unexpected chloro-bridged dipalladium complex; [Pd(PPh2O)(PPh2OH)(mu-Cl)](2) (7), whereas similar reaction with [Pt(COD)Cl-2] gives cis[Pt(C10H7OPPh2)(2)Cl-2] (8) in good yield

Group 11 metal complexes of the mesocyclic thioether aminophosphonites [-OC10H6(mu-S)C10H6O-]PNC4H8E (E = O, NMe)

Group 11 metal complexes of the mesocyclic thioether aminophosphonites [-OC10H6(mu-S)C10H6O-]PNC4H8E {2a: E = O; 2b: E = NMe; IUPAC names: 4-(dinaphtho[2,1-d:1',2'-g][1,3,6,2]dioxathiaphosphocin-4-yl)morpholine (2a), 1-(dinaphtho[2,1-d:1',2'-gl[1,3,6,2]dioxathiaphosphocin-4-yl)- 4-methylpiperazine (2b)} are reported. Thioether aminophosphonites 2a and 2b react with CuX (X = Cl, Br, and I) in a 1:1 molar ratio to give the tricoordinate, dimeric complexes [{[{-OC10H6(mu-S)C10H6O-}PNC4H8E-kappa P]Cu(mu-X)}(2)] (4a: E = O, X = Cl; 4b: E NMe, X = Cl; 5a: E = O, X = Br; 5b: E = NMe, X = Br; 6a: E = O, X = I; 6b: E = NMe, X = I), whereas with 2:1 molar ratios monomeric complexes of the type [{[-OC10H6(mu-S)C10H6O-]PNC4H8O-kappa P)(2)CUX] (7a: E = O, X = Cl; 7b: E = NMe, X = Cl; 8a: E = O, X = Br; 8b: E = NMe, X = Br; 9a: E = O, X = I; 9b: E = NMe, X = I) are obtained in excellent yield. The PS-chelated cationic complexes [{[-OC10H6(mu-S)C10H6O-]PNC4H8E-kappa P,kappa S](2)Cu]BF4 (10a: E = O; 10b: E = We) are obtained when 2a and 2b are treated with half an equivalent of [(MeCN)(4)Cu]BF4. Similarly, the silver complexes [{[{-OC10H6(mu-S)C10H6O-}PNC4H8E-kappa P,kappa S]-AgCF3SO3}(2)] (11a: E = O: 11b: E = NMe) and [{[-OC10H6(mu-S)C10H6O-]PNC4H8E-kappa P,kappa S)Ag(PPh3)]CF3SO3 (12a: E = O; 12b: E = NMe) are synthesized by the treatment of thioether aminophosphonites 2a and 2b with AgOTf and [Ag(PPh3)][OTf], respectively. Reactions of 2a and 2b with [AuCl(SMe2)] produce the simple monomeric gold(I) complexes [{[-OC10H6(mu-S)C10H6O-]PNC4H8E-kappa P)AuCl] (13a: E = O; 13b: E = NMe). The iodo derivatives [{[-OC10H6(mu-S)C10H6O-]PNC4H8E-kappa P)AuI] (14a: E = O; 14b: E = NMe) are obtained by the halide-exchange reaction of 13a and 13b with CuI at room temperature. The structures of complexes 5a, 7a, 8a, 13a, 13b, and 14a are confirmed by single-crystal X-ray diffraction studies. In all of these complexes, the sulfur atom in the mesocyclic ring shows coordinative interaction towards the phosphorus atom, and in 5a, 7a, 8a, and 14a towards the metal center as well

Synthesis and reaction kinetics of Pd(1,5-cyclooctadiene)Cl2 with N,N′-methylene-bis(2-aminopyridyl): an efficient catalyst for Suzuki-cross-coupling reactions

An inexpensive bidentate ligand N,N′-methylene-bis(2-aminopyridyl) (1) has been synthesized. Reaction of 1 with [Pd(COD)Cl2] affords a stable chelate complex, [{NC5H4N(H)(μ-CH2)(H)NC5H4N-κN,κN}PdCl2] (2). The kinetics of the pseudo-unimolecular reaction of N,N′-methylene-bis(2-aminopyridyl) with Pd(1,5-cyclooctadiene)Cl2 has been studied over the range 3.0 less-than-or-equals, slant 103 [1] less-than-or-equals, slant 7.0 mol dm−3, 30 °C less-than-or-equals, slant t less-than-or-equals, slant 40 °C. The rate constants and equilibrium constants were calculated. Entropy and enthalpy of the reaction are found to be −42 ± 1 J K−1 mol−1 and 75 ± 1 kJ mol−1, respectively, which clearly indicates that the substitution reaction follows associative mechanism. The complex 2 was tested for the Suzuki-cross-coupling reaction of a variety of aryl halides with aryl boronic acids in methanol at room temperature or at 60 °C, giving generally high yields for both activated and inactivated aryl bromides. The effect of solvents as well as the effect of base on the Suzuki-coupling reaction is also investigated.© Elsevie

Derivatisation and transition metal chemistry of a new monophosphinite ligand: 2-(diphenylphosphinoxy)naphthyl

1390-1394Reaction of monophosphinite ligand, 2-(diphenylphosphinoxy) naphthyl, C10H7PPh2 (1) with elemental sulphur or selenium gives the corresponding sulphide C10H7OP(S)Ph2 (2) or selenide C10H7OP(Se)ph2 (3) derivatives. Reaction of 1 with [CpRu(PPh3)2Cl] gives monosubstituted complex, [CpRu(C10H7OPPh2)(PPh3)C1] (4) as well as the disubstituted complex. [CpRu(C10H7PPh2)2Cl] (5) depending upon the reaction conditions. Treatment of 1 with [Rh(CO)2Cl]2 affords a trans-complex, [Rh(CO)(C10H7PPh2Cl] (6). Reaction of 1 with [Pd(COD)Cl2] results in the formation of an unexpected chlorobridged dipalladium complex: [Pd (PPh2O)( PPh2OH)(μ-Cl)]2 (7), whereas similar reaction with [pt(COD)Cl2] gives cis-[Pt(C10H7PPh2)2Cl2] (8) in good yield