摘要:
Methods for the preparation of saturated imidazolinium salts and related compounds that comprises reaction of formamidines with compounds such as dihaloethane and an optional base are disclosed. Alternatively, the imidazolinium salts and related compounds can be prepared in a one-step process without purification of the formamidine reactant. These methods make it possible to obtain numerous imidazolinium salts and related compounds under solvent-free reaction conditions and in excellent yields.
摘要:
Methods for the preparation of saturated imidazolinium salts and related compounds that comprises reaction of formamidines with compounds such as dihaloethane and an optional base are disclosed. Alternatively, the imidazolinium salts and related compounds can be prepared in a one-step process without purification of the formamidine reactant. These methods make it possible to obtain numerous imidazolinium salts and related compounds under solvent-free reaction conditions and in excellent yields.
摘要:
This invention relates generally to olefin metathesis, more particularly, to tri- or tetra-substituted imidazolinium salts which are precursors to N-heterocyclic carbene (NHC) ligands with tri- or tetra-substituted imidazolinium rings, organometallic ruthenium complexes comprising gem di-substituted imidazolinium NHC ligands, organometallic ruthenium complexes comprising tri- or tetra-substituted imidazolinium NHC ligands, and to olefin metathesis methods using them. The catalysts and methods of the invention have utility in the fields of catalysis, organic synthesis, and industrial chemistry.
摘要:
This invention relates generally to olefin metathesis, more particularly, to tri- or tetra-substituted imidazolinium salts which are precursors to N-heterocyclic carbene (NHC) ligands with tri- or tetra-substituted imidazolinium rings, organometallic ruthenium complexes comprising gem di-substituted imidazolinium NHC ligands, organometallic ruthenium complexes comprising tri- or tetra-substituted imidazolinium NHC ligands, and to olefin metathesis methods using them. The catalysts and methods of the invention have utility in the fields of catalysis, organic synthesis, and industrial chemistry.
摘要:
Described herein are compounds and methods of catalyzing ethenolysis reactions, optionally on an industrial scale. In certain embodiments, the catalysts bear cyclic alkyl amino carbene (CAAC) ligands with an ortho substituent, such as a methyl substituent, on an N-aryl ring. When used to catalyze ethenolysis reactions, certain such compounds produce a turnover number greater than 50,000.
摘要:
The disclosure concerns altering the mechanical and/or chemical property of a body tissue, particularly an ocular tissue. In specific cases, it concerns altering or stabilizing the shape of the cornea, such as in a subject suffering or at risk for ectasia or keratoconus. In other specific cases, it concerns strengthening the sclera in a subject suffering or at risk for myopia. The invention employs light irradiation of a photoactivatable compound, such as one that applies crosslinking to the tissue, for example.
摘要:
The invention relates to ruthenium alkylidene complexes having an N-heterocyclic carbene ligand comprising a 5-membered heterocyclic ring having a carbenic carbon atom and at least one nitrogen atom contained within the 5-membered heterocyclic ring, wherein the nitrogen atom is directly attached to the carbenic carbon atom and is substituted by a phenyl ring, and wherein the phenyl ring has a hydrogen at either or both ortho positions and is substituted at at least one ortho or meta position. The invention also relates to an olefin metathesis reactions and particularly to the preparation of tetra-substituted cyclic olefins via a ring-closing metathesis.
摘要:
Ruthenium and osmium carbene compounds that are stable in the presence of a variety of functional groups and can be used to catalyze olefin metathesis reactions on unstrained cyclic and acyclic olefins are disclosed. Also disclosed are methods of making the carbene compounds. The carbene compounds are of the formula where M is Os or Ru; R1 is hydrogen; R is selected from the group consisting of hydrogen, substituted or unsubstituted alkyl, and substituted or unsubstituted aryl; X and X1 are independently selected from any anionic ligand; and L and L1 are independently selected from any neutral electron donor. The ruthenium and osmium carbene compounds of the present invention may be synthesized using diazo compounds, by neutral electron donor ligand exchange, by cross metathesis, using acetylene, using cumulated olefins, and in a one-pot method using diazo compounds and neutral electron donors. The ruthenium and osmium carbene compounds of the present invention may be used to catalyze olefin metathesis reactions including, but not limited to, ROMP, RCM, depolymerization of unsaturated polymers, synthesis of telechelic polymers, and olefin synthesis.
摘要:
Novel blends of photo-initiators and photo-absorbers are disclosed. By the proper selection of the type and amount of absorber and initiator used in a composition, it is possible to regulate the conditions under which photo-induced reactions occur. In a specific embodiment, blends of UV initiators and photoabsorbers are used to control the conditions under which UV initiated polymerization occurs.
摘要:
The present invention provides engineered proteins and biomedical products made from the engineered proteins. The biomedical products include lenses useful for ophthalmic purposes.