Abstract: The present disclosure relates to an asymmetric process for preparing nicotine without protection, in particular to a process for preparing optically pure nicotine by taking nicotinate as a starting material and carrying out four-step reaction. The process comprises the following steps: nicotinate and ?-butyrolactone are subjected to condensation reaction, asymmetric catalytic reduction reaction, activation, and reaction with methylamine to give optically pure nicotine. The asymmetric catalytic reduction for preparing the chiral alcohol intermediate compound with high optical activity is a key step of the method.

Abstract: A sacubitril intermediate, a preparation method therefor, and use thereof. A key intermediate N-Boc amino alcohol represented by formula (10) or formula (10-a) can be efficiently prepared. The intermediate can be used to prepare a neutral endopeptidase (NEP) inhibitor or a prodrug thereof, particularly a NEP inhibitor comprising a skeleton of ?-amino-?-biphenyl-?-methylalkanoic acid or ester, such as sacubitril. Also provided are intermediates for preparing formula (10) or formula (10-a).

Abstract: The present invention relates to a preparation method of chiral primary amine. The chiral primary amine is prepared through a one-pot method that under the action of a ruthenium-chiral diphosphine catalyst, a simple ketone and an ammonium salt RCOONH4 have reductive amination by adding hydrogen and then are heated and hydrolyzed by adding acid.

Abstract: The present invention relates to the technical field of chiral synthesis, and specifically provides the synthesis and use of a new type of oxa-spirodiphosphine ligands. The bisphosphine ligand is prepared with oxa-spirobisphenol as a starting material after triflation, palladium catalyzed coupling with diaryl phosphine oxide, reduction of trichlorosilane, further palladium catalyzed coupling with diaryl phosphine oxide, and further reduction of trichlorosilane. The oxa-spiro compound has central chirality, and thus includes L-oxa-spirodiphosphine ligand and R-oxa-spirodiphosphine ligand. The racemic spirodiphosphine ligand is capable of being synthesized from racemic oxa-spirobisphenol as a raw material. The present invention can be used as a chiral ligand in the asymmetric hydrogenation of unsaturated carboxylic acids. The complex of the ligand with ruthenium can achieve an enantioselectivity of greater than 99% in the asymmetric hydrogenation of methyl-cinnamic acid.

Abstract: The present invention relates to the technical field of chiral synthesis, and specifically provides a new type of oxa-spirodiphosphine ligands. The bisphosphine ligand is prepared with oxa-spirobisphenol as a starting material after triflation, palladium catalyzed coupling with diaryl phosphine oxide, reduction of trichlorosilane, further palladium catalyzed coupling with diaryl phosphine oxide, and further reduction of trichlorosilane. The oxa-spiro compound has central chirality, and thus includes L-oxa-spirodiphosphine ligand and R-oxa-spirodiphosphine ligand. The racemic spirodiphosphine ligand is capable of being synthesized from racemic oxa-spirobisphenol as a raw material. The present invention can be used as a chiral ligand in the asymmetric hydrogenation of unsaturated carboxylic acids. The complex of the ligand with ruthenium can achieve an enantioselectivity of greater than 99% in the asymmetric hydrogenation of methyl-cinnamic acid.

Abstract: The invention relates to a micro-encapsulated self-repairing polymerizable composition that comprises at least one selected polymerizable compound to be integrated into organic, inorganic or composite materials for the self-repairing of damages incurred in the use conditions thereof, characterised in that micro-encapsulated polymerizable composition is integrated alone into said materials and, after the release of the microcapsule and in the absence of a catalyst, spontaneously polymerises in the presence of a polymerisation-triggering agent that is absent in said materials but naturally occurs during the use thereof, thus repairing said damages.

Abstract: The present invention relates to the preparation of compounds of formula (I) derived from arylacetic acid comprising two phenol functions and an amide function, which have free-radical scavenging and antioxidant properties and which are soluble in lipid media. These compounds can be used as cosmetic and pharmaceutical preparations for the prevention of biological degradations caused by free radicals.

Abstract: The invention relates to antimicrobial non-cross-linked polymers which are constituted of an ester and/or amide resin to which quaternary ammonium salts are bound by a covalent bond which is potentially reactive with water, the quaternary ammonium content being at least 1 M/kg, a well as to the use thereof for the preparation of a material having antimicrobial properties and to their methods of preparation.

Abstract: Particular mixed vanadium/other metal catalysts, well suited for the desulfurization of gaseous effluents containing contaminating amounts of objectionable sulfur compounds, typically via the Claus reaction and notably in the presence of oxygen, comprise a support substrate, e.g., titanium dioxide, having an active catalytic phase deposited thereon, such active catalytic phase being constituted of an electroneutral solid solution having the average composition:A.sub.4.+-.y V.sub.2.+-.x O.sub.9in which A is a metal other than vanadium, e.g., magnesium, calcium or zinc, 0.ltoreq.x.ltoreq.0.2 and 0.ltoreq.y.ltoreq.0.5.

Abstract: The desulfurization of gaseous effluents containing contaminating amounts of objectionable sulfur compounds, typically via the Claus reaction and notably in the presence of oxygen, utilizing a support substrate, e.g., titanium dioxide, having an active catalytic phase deposited thereon, such active catalytic phase being constituted of an electroneutral solid solution having the average composition:A.sub.4.+-.y V.sub.2.+-.x O.sub.9in which A is a metal other than vanadium, e.g., magnesium, calcium or zinc, 0.ltoreq.x.ltoreq.0.2 and 0.ltoreq.y.ltoreq.0.5.

Abstract: Particular mixed vanadium/other metal catalysts, well suited for the desulfurization of gaseous effluents containing contaminating amounts of objectionable sulfur compounds, typically via the Claus reaction and notably in the presence of oxygen, comprise a support substrate, e.g., titanium dioxide, having an active catalytic phase deposited thereon, such active catalytic phase being constituted of an electroneutral solid solution having the average composition:A.sub.4.+-.y V.sub.2.+-.x O.sub.9in which A is a metal other than vanadium, e.g., magnesium, calcium or zinc, 0.ltoreq.x.ltoreq.0.2 and 0.ltoreq.y.ltoreq.0.5.

Abstract: Multiple purpose catalysts adapted for the treatment of internal combustion engine exhaust gases comprise a particulate refractory oxide support, e.g., alumina particles, having an active catalytic phase deposited thereon, said active catalytic phase including zirconium, cerium and platinum, and optionally iridium, rhodium, palladium and other metal values.

Abstract: Multiple purpose catalysts adapted for the treatment of internal combustion engine exhaust gases comprise a particulate refractory oxide support, e.g., alumina particles, having an active catalytic phase deposited thereon, said active catalytic phase including zirconium, cerium and platinum, and optionally iridium, rhodium, palladium and other metal values.

Abstract: Carbon monoxide is reacted with water vapor and converted into hydrogen and carbon dioxide, in the presence of a thio-resistant catalyst which comprises an active phase deposited onto a support, said active phase comprising molybdenum, vanadium or tungsten, and a cobalt and/or nickel promoter therefor, and said support comprising cerium oxide or zirconium oxide. The reaction mixture advantageously includes carbon monoxide, hydrogen, water and compounds of sulfur, wherefrom hydrogen is selectively produced in increased amounts.

Abstract: Thermally stable, sulfur-resistant catalysts for the conversion of exhaust gases from internal combustion engines includes an inert, rigid support substrate, e.g., a cellular monolith, coated with a layer of porouse material, the porous material containing alumina, at least one rare earth oxide, and a spinel type compound having a specific surface of at least 50 m.sup.2 /g, and the support substrate having an effective amount of a catalytically active phase impregnated onto the porous coating thereof.

Abstract: Improvedly time-stable catalysts adopted for the treatment of internal combustion engine exhaust gases include a monolithic catalyst support impregnated with a plurality of catalytically active phases, one section of the support being impregnated with a first catalytically active phase and remaining section of the support being impregnated with a second catalytically active phase.

Abstract: Carbon monoxide is reacted with water vapor and converted into hydrogen and carbon dioxide, in the presence of a thio-resistant catalyst which comprises an active phase deposited onto a support, said active phase comprising molybdenum, vanadium or tungsten, and a cobalt and/or nickel promoter therefor, and said support comprising cerium oxide or zirconium oxide. The reaction mixture advantageously includes carbon monoxide, hydrogen, water and compounds of sulfur, wherefrom hydrogen is selectively produced in increased amounts.

Abstract: Carbon monoxide is reacted with water vapor and converted into hydrogen and carbon dioxide, in the presence of a thio-resistant catalyst which comprises an active phase deposited onto a support, said active phase comprising molybdenum, vanadium or tungsten, and a cobalt and/or nickel promoter therefor, and said support comprising cerium oxide or zirconium oxide. The reaction mixture advantageously includes carbon monoxide, hydrogen, water and compounds of sulfur, wherefrom hydrogen is selectively produced in increased amounts.

Abstract: The invention relates to a new hydrocarbon hydroconversion catalyst, which is a mixture of an amorphous matrix, a zeolite and at least one metal of Group VIII and optionally of Group VI, the zeolite having a SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of about between 8 and 70, a sodium content of less than 0.15% by weight, a unit mesh parameter a.sub..degree. of between 24.55 and 24.24.times.10.sup.-10 m, a sodium ion recovery capacity C.sub.Na, expressed in grams of sodium per 100 grams of modified zeolite, greater than 0.85, a specific surface area greater than 400 m.sup.2 g.sup.-1, a water vapor adsorption capacity at 25.degree. C. (with a P/Po ratio of 0.10) greater than 6% by weight, a pore distribution between 1 and 20% of the pore volume contained essentially in pores of diameters between 20 and 80.times.10.sup.-10m, the remaining pore volume being contained essentially in pores of diameters less than 20.times.10.sup.-10 m, the matrix being characterized by the following textural properties:S.gtoreq.

Abstract: A multifunctional pollution control catalyst for the treatment of exhaust gases from internal combustion engines is comprised of a catalyst support having an active catalytic phase deposited thereon, said active catalytic phase comprising catalytically effective amounts of (i) zirconium, (ii) cerium, (iii) palladium, (iv) iridium and/or rhodium, and, optionally, (v) iron.