Patents by Inventor Meng-Sheng Ao

Meng-Sheng Ao has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5434324
    Abstract: Alkyl substituted cyclopentadienes are prepared by reacting cyclopentenones with a Grignard reagent followed by the acidification and dehydration of the resulting tertiary alcohol with an organic carboxylic acid.
    Type: Grant
    Filed: October 15, 1993
    Date of Patent: July 18, 1995
    Assignee: Albemarle Corporation
    Inventors: John Y. Lee, Meng-Sheng Ao
  • Patent number: 5302733
    Abstract: A racemic mixture of a chiral, silicon bridged transition metal metallocene, which is substantially free of meso isomer, is precipitated directly from a reaction mixture as it is formed by reacting an organic solvent solution of an alkali metal salt of a silicon bridged ligand with a transition metal tetrahalide-ether complex.
    Type: Grant
    Filed: March 30, 1992
    Date of Patent: April 12, 1994
    Assignee: Ethyl Corporation
    Inventors: Steven P. Diefenbach, Meng-Sheng Ao, John M. Power, Jamie R. Strickler
  • Patent number: 5276199
    Abstract: A process for preparing a cyclopentenone by forming a two-phase mixture of a 1,4-diketone, a water immiscible organic solvent, and an aqueous base solution, and heating the mixture so as to convert the 1,4-diketone to a cyclopentenone which collects in the organic solvent phase.
    Type: Grant
    Filed: February 11, 1993
    Date of Patent: January 4, 1994
    Assignee: Ethyl Corporation
    Inventors: John Y. Lee, Meng-Sheng Ao, Stephen E. Belmont
  • Patent number: 5254707
    Abstract: The process for preparing a compound of the formula:Cp'YNHRwherein: Cp' is a cyclopentadienyl or a substituted cyclopentadienyl group, Y is a covalent bridging group which contains one or more group 14 elements, and R is a C.sub.1 to C.sub.20 hydrocarbyl or substituted hydrocarbyl group, the process comprising reacting a ligand of the formula Cp'YX, wherein Cp' and Y are as defined above and X is halogen, with a substantially equimolar amount of a primary amine of the formula NH.sub.2 R, wherein R is as defined above, in an inert solvent in the presence of a HX scavenger at an elevated temperature of at least about 35.degree. C., so as to form said compound.
    Type: Grant
    Filed: December 7, 1992
    Date of Patent: October 19, 1993
    Assignee: Ethyl Corporation
    Inventors: Jamie R. Strickler, John M. Power, Meng-Sheng Ao
  • Patent number: 5136075
    Abstract: Phosphorus compounds having at least one chlorine, bromine or iodine bonded directly to phosphorus are transhalogenated with fluorine by reaction with anhydrous hydrogen fluoride in an inert solvent, e.g., xylene, methylene chloride, in a manner such that said anhydrous hydrogen fluoride is added to said phosphorus compound at a rate such that said anhydrous hydrogen fluoride reacts with said phosphorus compound without the accumulation of an amount of unreacted anhydrous hydrogen fluoride which is sufficient to cause substantial decomposition of the desired fluorophosphorus product. A catalytic amount of a pyridine-type compound may optionally included in the reaction.
    Type: Grant
    Filed: July 1, 1991
    Date of Patent: August 4, 1992
    Assignee: Ethyl Corporation
    Inventors: Edward A. Burt, Lester P. J. Burton, Meng-Sheng Ao, Barbara C. Stahly
  • Patent number: 5061818
    Abstract: Phosphorus compounds having at least one chlorine, bromine or iodine bonded directly to phosphorus are transhalogenated with fluorine by reaction with a fluoride salt, e.g., KF, or ammonium fluoride in the presence of a hydrogen halide salt of a pyridine-type nitrogen base, e.g., pyridine hydrochloride.
    Type: Grant
    Filed: October 19, 1987
    Date of Patent: October 29, 1991
    Assignee: Ethyl Corporation
    Inventors: Lester P. J. Burton, Meng-Sheng Ao
  • Patent number: 5049691
    Abstract: Phosphorus compounds having at least one chlorine, bromine or iodine bonded directly to phosphorus are transhalogenated with fluorine by reaction with anhydrous hydrogen fluoride in an inert solvent, e.g., xylene, methylene chloride, in a manner such that said anhydrous hydrogen fluoride is added to said phosphorus compound at a rate such that said anhydrous hydrogen fluoride reacts with said phosphorus compound without the accumulation of an amount of unreacted anhydrous hydrogen fluoride which is sufficient to cause substantial decomposition of the desired fluorophosphorus product.
    Type: Grant
    Filed: March 5, 1990
    Date of Patent: September 17, 1991
    Assignee: Ethyl Corporation
    Inventors: Edward A. Burt, Lester P. J. Burton, Meng-Sheng Ao, Barbara C. Stahly
  • Patent number: 4929745
    Abstract: Phosphorus compounds having at least one chlorine, bromine or iodine bonded directly to phosphorus are transhalogenated with fluorine by reaction with a hydrogen fluoride salt of a pyridine-type nitrogen base, e.g. pyridine hydrofluoride in an inert solvent.
    Type: Grant
    Filed: August 1, 1988
    Date of Patent: May 29, 1990
    Assignee: Ehtyl Corporation
    Inventors: Kestutis A. Keblys, Meng-Sheng Ao, Lester P. J. Burton
  • Patent number: 4778933
    Abstract: The process comprises: (a) initiating a feed of molten diphenyl oxide to a substantially anhydrous mixture of methylene dibromide solvent, elemental bromine (Br.sub.2) and an aluminum trihalide catalyst at a temperature between about 10.degree. and about 30.degree. C.; (b) heating the reaction mixture to about 50.degree.-60.degree. C., and while maintaining the temperature at about 50.degree.-60.degree. C., continuing the feed of molten diphenyl oxide until the total amount fed is equivalent to (i) about 0.064 to about 0.077 mole per mole of elemental bromine (Br.sub.2) employed in the reaction, and (ii) about 0.2 to about 10 parts by weight per part by weight of methylene dibromide employed in the reaction; (c) steam distilling the methylene dibromide solvent and the residual bromine from the reaction mixture; (d) recovering decabromodiphenyl oxide from the distilland; and (e) drying the methylene dibromide and bromine distillate to render them suitable for reuse in the process.
    Type: Grant
    Filed: July 15, 1987
    Date of Patent: October 18, 1988
    Assignee: Ethyl Corporation
    Inventors: Bonnie G. McKinnie, Meng-Sheng Ao