Showing papers in "Journal of The Chemical Society, Chemical Communications in 1991"
TL;DR: The order of the change in π-A isotherms being similar to that of the extractability was also observed in this article for m-1 and p-Hexadecyloxyphenylboronic acids.
Abstract: m- and p-Hexadecyloxyphenylboronic acids (m-1 and p-1, respectively) selectively extract saccharides; the monolayer of m-1 at the air–water interface selectively responds to these saccharides, the order of the change in π–A isotherms being similar to that of the extractability
193 citations
TL;DR: In this paper, cholesterol derivatives containing a benzocrown ether moiety or an azobenzene moiety coupled to C-3 of a steroidal moiety through an ester linkage are synthesized; some of them act as thermally reversible gelators of organic fluids and show novel light and metal-responsive functions.
Abstract: Cholesterol derivatives containing a benzocrown ether moiety or an azobenzene moiety coupled to C-3 of a steroidal moiety through an ester linkage are synthesized; some of them act as thermally reversible gelators of organic fluids and show novel light- and metal-responsive functions.
181 citations
Abstract: An approach to molecular wires based on quasi-one-dimensional linearly conjugated poly-porphyrin systems is outlined and a rationally designed synthesis of the tetrakisporphyrin 9, a strand some 65 A in length, via the bis(porphyrin)tetraone 2 is described.
173 citations
TL;DR: In this paper, high-order stable structures with planar tetracoordinate central atoms, such as Al4O, Al4N, Al3SiN, cis-Al2Si2C, trans-Al 2Si2c and AlSi3B, are predicted at the MP4SDTQ/6-311 + G*/MP2(full)/6-31G* level.
Abstract: Highly stable structures with planar tetracoordinate central atoms, Al4O, Al4N–, Al3SiN, cis-Al2Si2C, trans-Al2Si2C and AlSi3B, are predicted computationally at the ab initio MP4SDTQ/6-311 + G*//MP2(full)/6-31G* level.
167 citations
TL;DR: In the presence of the co-catalyst NaOH (2.4 mol%), RuCl2(PPh3)3(0.1 mol%) catalyses efficient transfer hydrogenation of both aliphatic and aromatic ketones by propan-2-ol with rates up to 900 turnovers per hour at 82 °C; no hydrogenation occurs in the absence of sodium hydroxide as discussed by the authors.
Abstract: In the presence of the co-catalyst NaOH (2. 4 mol%), RuCl2(PPh3)3(0.1 mol%) catalyses efficient transfer hydrogenation of both aliphatic and aromatic ketones by propan-2-ol with rates up to 900 turnovers per hour at 82 °C; no hydrogenation occurs in the absence of sodium hydroxide.
154 citations
TL;DR: Aerobic oxidation of primary alcohols to aldehydes occurs under mild conditions at 20 °C via a triple catalytic system consisting of RuCl(OAc)(PPh3)3-hydroquinone-Co(salophen) as mentioned in this paper, H2salophen =N,N′-bis(salicylidene)-o-phenylenediamine.
Abstract: Aerobic oxidation of primary alcohols to aldehydes occurs under mild conditions at 20 °C via a triple catalytic system consisting of RuCl(OAc)(PPh3)3–hydroquinone–Co(salophen)(PPh3)[H2salophen =N,N′-bis(salicylidene)-o-phenylenediamine].
152 citations
TL;DR: In this article, 2,3-Bis-n-decyloxyanthracene can form thermoreversible gels with alcohols at very low concentrations, and the network of the gel consists of head-to-tail assemblies of the aromatic component coexisting with the alcohol, the organization of the system essentially relying upon dipolar forces and van der Waals interactions.
Abstract: 2,3-Bis-n-decyloxyanthracene can form thermoreversible gels with alcohols at very low concentrations; electronic absorption spectra and fluorescence emission studies suggest that the network of the gel consists of head-to-tail assemblies of the aromatic component coexisting with the alcohol, the organization of the system essentially relying upon dipolar forces and van der Waals interactions.
145 citations
TL;DR: The proportion of non-ionic, metal free, organic compounds that crystallise as hydrates increases, within the class, with an increase in the number of hydrogen-bond acceptor groups with respect to the donor groups as mentioned in this paper.
Abstract: The proportion of non-ionic, metal free, organic compounds that crystallise as hydrates increases, within the class, with an increase in the number of hydrogen-bond acceptor groups with respect to the donor groups.
141 citations
TL;DR: An electroactive polymer with a lowered band gap was obtained from the monomer cyclopenta[2,1-b;3,4-b′]dithiophen-4-one as discussed by the authors.
Abstract: An electroactive polymer with a lowered band gap has been obtained from the monomer cyclopenta[2,1-b;3,4-b′]dithiophen-4-one.
136 citations
TL;DR: An electroactive polymer with a bandgap of ≈ 0.8 eV has been obtained from the monomer 4-dicyanomethylene-4H-cyclopenta[2,1-b;3,4-b′]dithiophene as discussed by the authors.
Abstract: An electroactive polymer with a bandgap of ≈0.8 eV has been obtained from the monomer 4-dicyanomethylene-4H-cyclopenta[2,1-b;3,4-b′]dithiophene.
132 citations
TL;DR: In this paper, a single line 19F NMR spectrum of solid C60 with fluorine gas is used to give, after twelve days (10 mg scale), a colourless derivative indicated by a single-line 19F spectrum to be C60F60; reaction time is quantity dependent.
Abstract: Fluorination of solid C60 with fluorine gas proceeds in a stepwise manner to give, after twelve days (10 mg scale), a colourless derivative indicated by a single line 19F NMR spectrum to be C60F60; reaction time is quantity dependent.
TL;DR: The colloidal fibrils of polyaniline-poly(acrylic acid) complex were first synthesized by template guided chemical polymerization; their morphology and the electronic absorption spectra in aqueous solution were reported.
Abstract: The colloidal fibrils of polyaniline–poly(acrylic acid) complex were first synthesized by template guided chemical polymerization; their morphology and the electronic absorption spectra in aqueous solution are reported.
TL;DR: In this paper, a strong green-coloured 1 : 1 complex with the π-electron accepting tetracationic cyclophane, cyclobis(Paraquat-p-phenylene), in both the solid and solution states is demonstrated.
Abstract: The powerful π-electron donor, tetrathiafulvalene, forms a strong green-coloured 1 : 1 complex with the π-electron accepting tetracationic cyclophane, cyclobis(Paraquat-p-phenylene), in both the solid and solution states as demonstrated by X-ray crystallography and spectroscopy (NMR and UV–VIS), respectively.
TL;DR: In this paper, pyrophoric strontium powder in tetrahydrofuran with ArOH (Ar = C6H2But3-2,4,6) or HNR′2 at ambient temperature affords crystalline [Sr(OAr)2(THF)4] or [Srin(NR′ 2)2 (THF), respectively, and 3 with 1,4-dioxane yields crystalline
Abstract: Treatment of pyrophoric strontium powder in tetrahydrofuran with ArOH (Ar = C6H2But3-2,4,6) or HNR′2 at ambient temperature affords crystalline [Sr(OAr)2(THF)4] or [Sr(NR′2)2(THF)2]3, respectively, and 3 with 1,4-dioxane yields crystalline [{trans-Sr(NR′2)2(µ-1,4-dioxane)}∞]4; co-condensation of calcium vapour and RBr in THF at 77 K affords [CaR2(THF)3]5, which with 1,4-dioxane gives [CaR2(1,4-dioxane)2]6; X-ray structures reveal the alkaline earth metal environment to be square-planar for 4[Sr-N 2.449(7), Sr-O 2.533(9)A] but tetrahedral for 6[Ca-C 2.483(5), Ca-O 2.373(4)A] with dioxane as a bridging bidentate 4 or monodentate 6 ligand.
Journal Article•
TL;DR: The structure of Zn[C(CN)3]2 consists of two independent infinite rutile-related frameworks whose compiex entanglement resembles 3D knitting.
Abstract: The structure of Zn[C(CN)3]2 consists of two independent infinite rutile-related frameworks whose compiex entanglement resembles 3D knitting.
TL;DR: In this paper, a modified USY-zeolite which contains profuse supermicropores was used for the hydrogenation of N-acyldehydrophenylalanine derivatives.
Abstract: Rh-complexes with N-based chiral ligands, when anchored on a modified USY-zeolite which contains profuse supermicropores, produce a remarkable increase of enantioselectivity (>95%) in the hydrogenation of N-acyldehydrophenylalanine derivatives and represent a truly heterogeneous counterpart of the homogeneous organometallic catalysts.
TL;DR: In this article, a diphosphite derived from R-2,2′-binaphthol and its nickel(0) complex is described, and optical yields for the hydrocyanation of norbornene are 38%.
Abstract: The new diphosphite 1 derived from R-2,2′-binaphthol and its nickel(0) complex are described; optical yields for the hydrocyanation of norbornene are 38%.
TL;DR: In this paper, the crystal structure of the macrccyclic tetraphenol p-tert-butylcalix was determined and the metal atom was found to be bound within the cup formed by the ligand, indicating that it is involved in polyhapto bonding to a delocalised anionic ligand.
Abstract: Determination of the crystal structure of the mono-caesium derivative of the macrccyclic tetraphenol p-tert-butylcalix[4]arene shows the metal atom to be bound within the cup formed by the ligand; the metal is thereby in much closer proximity to the aromatic carbon atoms than to the phenolic oxygens, indicating that it is involved in polyhapto bonding to a delocalised anionic ligand.
TL;DR: In this paper, the mechanism of this reaction has been elucidated based on reactions of 1 with vinylsilanes as well as those of the resulting ruthenium-silyl complex with alkenes.
Abstract: Selective cross-disproportion between vinylsilanes and various mono-substituted alkenes is catalysed by [RuCl(CO)H(PPh3)3]1; the mechanism of this reaction has been elucidated based on reactions of 1 with vinylsilanes as well as those of the resulting ruthenium–silyl complex with alkenes.
TL;DR: Treatment of the complexes trans-[M(PBu3)2Cl2](M = Ni, Pd or Pt) with one equivalent of the reagent Me3SnCC–R–CCSnMe3(R =p-C6H4) affords the polymeric species trans-[–M( PBu 3)2-CC– R–CC–]n, where as if two equivalents of the tin reagent are used in this reaction.
Abstract: Treatment of the complexes trans-[M(PBu3)2Cl2](M = Ni, Pd or Pt) with one equivalent of the reagent Me3SnCC–R–CCSnMe3(R =p-C6H4) affords the polymeric species trans-[–M(PBu3)2-CC–R–CC–]n, where as if two equivalents of the tin reagent are used in this reaction, when M = Pt, the complex trans-[Me3SnCC–R–CC–Pt(PBu3)2-CC–R–CCSnMe3] may be isolated, a precursor for further syntheses; the complex mer-trans-[Rh(PMe3)3(SnMe3)(CCPh)2] has been prepared by the addition of Me3SnCCPh to [Rh(PMe3)4][Cl], and this latter species, when treated with Me3SnCC–R′–CCSnMe3(R′=p-C6H4–C6H4–p), affords the oligomeric compound mer-trans-[–Rh(PMe3)3(SnMe3)–CC–R′–CC–]n.
TL;DR: The structures of four hydroxylated unsaturated C18 fatty acids (psi factors) which induce premature sexual sporulation in A. nidulans, and the enantioselective synthesis of two of the components, psiBα and psiBβ, are described.
Abstract: The structures of four hydroxylated unsaturated C18 fatty acids (psi factors) which induce premature sexual sporulation in A. nidulans, and the enantioselective synthesis of two of the components, psiBα and psiBβ, are. described.
TL;DR: The sterically crowded cis-[Ru(dmp)2S2]-PF6]2 (dmp = 2,9 dirnethyl-1,10-phenanthroline, S = Me3CN or H2O) is capable of hydroxylating methane under mild reaction conditions utilizing Ruthenium(VI) as the primary oxidant.
Abstract: The sterically crowded cis-[Ru(dmp)2S2](PF6)2(dmp = 2,9 dirnethyl-1,10-phenanthroline, S = Me3CN or H2O) is capable of hydroxylating methane under mild reaction conditions utilizing H2O2 as the primary oxidant; oxidation of this complex with H2O2 is studied spectrophotometrically by UV–VIS and NMR spectroscopy implicating ruthenium(VI) as the active oxidant.
TL;DR: 2,6-Diisopropylnaphthalene is selectively produced in the liquid phase alkylation of naphalene with propene or propan-2-ol over H-mordenite catalyst as mentioned in this paper.
Abstract: 2,6-Diisopropylnaphthalene is selectively produced in the liquid phase alkylation of naphthalene with propene or propan-2-ol over H-mordenite catalyst.
TL;DR: In this article, the synthesis and X-ray crystal structure of a nitrogen-bridged linear trinuclear copper complex with extremely short Cu-Cu bond distances [2.4712(4)A] and tridentate dipyridylamido ligands was reported.
Abstract: The synthesis and X-ray crystal structure of a nitrogen-bridged linear trinuclear copper complex [Cu3(dpa)4Cl2]{dpa = di-2-pyridylamido, [(C5H4)2N]–}, with extremely short Cu–Cu bond distances [2.4712(4)A] and tridentate dipyridylamido ligands in a novel syn-syn conformation are reported.
TL;DR: In this article, the principal structural features of multinuclear complexes of cadmium(II) with the plant-peptide phytochelatin have been deduced from extended X-ray absorption fine structure (EXAFS) data: (i) Cd(SCys)4 coordination, (ii) in contrast to Cd-metallothioneins, no formation of Cadmium 'clusters' and (iii) non-coordinating carboxylate groups.
Abstract: The principal structural features of multinuclear complexes of cadmium(II) with the plant-peptide phytochelatin have been deduced from Cd-EXAFS (EXAFS = extended X-ray absorption fine structure) data: (i) Cd(SCys)4 coordination, (ii) in contrast to Cd-metallothioneins, no formation of cadmium ‘clusters’ and (iii) non-coordinating carboxylate groups.
TL;DR: In this article, it was shown that the regioselectivity in the reaction of styrene depends to a considerable extent on the substituents of the silanes, and that the reaction can be improved by adding di- or tri-hydrosilanes.
Abstract: [(C5Me5)2NdH]2 and (C5Me5)2NdCH(SiMe3)2 effectively catalyse the hydrosilylation of alkenes with di- or tri-hydrosilanes at 30 to 80 °C; the regioselectivity in the reaction of styrene depends to a considerable extent on the substituents of the silanes.
TL;DR: A variety of usefully functionalised biaryls may be prepared under neutral conditions by an intramolecular free radical ipso substitution reaction at an sp2 sulphonyl substituted carbon atom; the overall efficiency of the process being determined both by the nature and number of atoms linking the two aromatic rings and by appropriately positioned substituents on the aromatic aceeptor ring.
Abstract: A variety of usefully functionalised biaryls may be prepared under neutral conditions by an intramolecular free radical ipso substitution reaction at an sp2 sulphonyl substituted carbon atom; the overall efficiency of the process being determined both by the nature and number of atoms linking the two aromatic rings and by appropriately positioned substituents on the aromatic aceeptor ring.
TL;DR: In this paper, 2,4-Dienes are prepared in high yields with high regioselectivity by the codimerisation of acetylenes and alkenes in the presence of a catalytic amount of Ru(cod)(cot) at 80 °C.
Abstract: 2,4-Dienes are prepared in high yields with high regioselectivity by the codimerisation of acetylenes and alkenes in the presence of a catalytic amount of Ru(cod)(cot) at 80 °C cod = cycloocta-1,5-diene, cot = cycloocta-1,3,5,-triene.
TL;DR: In this article, the synthesis, stability and hydrocyanation catalytic activity of nickel(0) complexes of the diphosphite 1 derived from 2,2′-biphenol are described.
Abstract: The synthesis, stability and hydrocyanation catalytic activity of nickel(0) complexes of the diphosphite 1 derived from 2,2′-biphenol are described; the X-ray crystal structures of the ligand 1 and its platinum(0) complex 2b are reported.