Patents by Inventor Gauri Sankar Lal

Gauri Sankar Lal 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: 7030283
    Abstract: This invention relates to a process for the preparation of 1,1-difluoroolefins, e.g., difluorovinyl cycloaliphatic compounds such as difluorovinylcyclohexane and derivatives by the dehydrofluorination of a trifluoromethyl-substituted cycloaliphatic compound and the resulting compositions. This method utilizes a “sterically hindered super-base” system represented by the formula M+?NRR?; where M is Na or K and R is a secondary, or tertiary alkyl or cycloalkyl group of amines for effecting dehydrofluorination of the trifluoromethyl group leading to the difluorovinyl based cycloaliphatic compounds. The sterically hindered super base can be formed by the, in situ, reaction of a sodium or potassium alkoxide, e.g., KtBuO with a lithium dialkylamide where the lithium is bonded to nitrogen atom of an amine bearing secondary or tertiary aliphatic groups.
    Type: Grant
    Filed: January 23, 2004
    Date of Patent: April 18, 2006
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Gauri Sankar Lal, Kathryn Sue Hayes, Guido Peter Pez
  • Patent number: 6958415
    Abstract: A new route has been found leading to the formation of pentafluorosulfuranyl arylenes. In its broadest aspect the process comprises: effecting dehydrohalogenation or dehydrogenation of a pentafluorosulfuranyl cycloaliphatic compound represented by either of the structures: wherein R1-5 are H, halogen, C1-10 alkyl, C1-10 alkoxy, C1-10 thionyl, C1-10 alkyl ether, aryl and substituted aryl, thioether, sulfonyl, carboalkoxy, alkylamino, arylamino, alkylphosphoryl, alkylphosphonyl, arylphosphonyl, arylphosphoryl, and mixtures thereof and X is a halogen atom to form the pentafluorosufuranyl arylene represented by the structures: wherein R1-R5 are as represented above.
    Type: Grant
    Filed: November 14, 2003
    Date of Patent: October 25, 2005
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Gauri Sankar Lal, Kristen Elaine Minnich
  • Patent number: 6894200
    Abstract: A method of preparing vicinal difluoro aromatic compounds in high yield from hydroxy aromatic compounds using various bases and a method of preparing intermediates thereof. A method for making a vicinal difluoro halogenated aromatic compound including providing a tetrafluoro derivative of a halogen substituted aromatic compound, wherein the tetrafluoro derivative has two fluorine atoms on each of two adjacent carbons and at least one additional halogen substituent; reacting the tetrafluoro derivative with a reducing agent in presence of a base for a reaction time sufficient to form the vicinal difluoro halogenated aromatic compound containing two vicinal fluorine substituents and the at least one additional halogen substituent, wherein the reducing agent is used in a reducing agent effective amount sufficient to retain the at least one additional halogen substituent.
    Type: Grant
    Filed: February 3, 2003
    Date of Patent: May 17, 2005
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Axel Klauck-Jacobs, Kathryn Sue Hayes, Reiner Taege, William Casteel, Gauri Sankar Lal
  • Patent number: 6870068
    Abstract: Addition of an SF5 group to organic compounds such as alkyl-substituted terminal alkenes, internal alkenes and cycloalkenes via the reaction with SF5Br is effected under liquid phase conditions and generally in the presence of a free radical initiator, preferably triethyl borane.
    Type: Grant
    Filed: November 14, 2003
    Date of Patent: March 22, 2005
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Gauri Sankar Lal, Kristen Elaine Minnich
  • Publication number: 20040115818
    Abstract: An apparatus for detecting a leak of a fluid from a vessel having an inner wall and an outer wall includes at least one chemical material layer adjacent the outer wall. At least a portion of the chemical material layer is adapted to undergo a chemical reaction with a portion of the fluid leaking through the outer wall. The apparatus may also include at least one semi-permeable material layer adjacent the chemical material layer. The fluid may be a pressurized gas, such as hydrogen or another gas that will react with the chemical material layer to produce a detectable odor and/or a detectable discoloration of the chemical material layer.
    Type: Application
    Filed: December 16, 2002
    Publication date: June 17, 2004
    Inventors: Pushpinder Singh Puri, Gauri Sankar Lal, John Matthew Fernbacher
  • Patent number: 6706933
    Abstract: A method of preparing vicinal difluoro aromatic compounds in high yield from hydroxy aromatic compounds and a method of preparing intermediates thereof. The hydroxy aromatic compound can be a mono-, bi- or tricyclic aromatic in which the rings are separate or fused. One or more of the rings can contain heteroatoms, such as oxygen, nitrogen, or sulfur, and can contain one or more substitutions, in addition to the hydroxy substitution.
    Type: Grant
    Filed: December 30, 2002
    Date of Patent: March 16, 2004
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Gauri Sankar Lal, Kathryn Sue Hayes
  • Publication number: 20030149315
    Abstract: A method of preparing vicinal difluoro aromatic compounds in high yield from hydroxy aromatic compounds using various bases and a method of preparing intermediates thereof. A method for making a vicinal difluoro halogenated aromatic compound including providing a tetrafluoro derivative of a halogen substituted aromatic compound, wherein the tetrafluoro derivative has two fluorine atoms on each of two adjacent carbons and at least one additional halogen substituent; reacting the tetrafluoro derivative with a reducing agent in presence of a base for a reaction time sufficient to form the vicinal difluoro halogenated aromatic compound containing two vicinal fluorine substituents and the at least one additional halogen substituent, wherein the reducing agent is used in a reducing agent effective amount sufficient to retain the at least one additional halogen substituent.
    Type: Application
    Filed: February 3, 2003
    Publication date: August 7, 2003
    Inventors: Axel Klauck-Jacobs, Kathryn Sue Hayes, Reiner Taege, William Casteel, Gauri Sankar Lal
  • Publication number: 20030100806
    Abstract: A method of preparing vicinal difluoro aromatic compounds in high yield from hydroxy aromatic compounds and a method of preparing intermediates thereof. The hydroxy aromatic compound can be a mono-, bi- or tricyclic aromatic in which the rings are separate or fused. One or more of the rings can contain heteroatoms, such as oxygen, nitrogen, or sulfur, and can contain one or more substitutions, in addition to the hydroxy substitution.
    Type: Application
    Filed: December 30, 2002
    Publication date: May 29, 2003
    Inventors: Gauri Sankar Lal, Kathryn Sue Hayes
  • Patent number: 6515191
    Abstract: A method of preparing vicinal difluoro aromatic compounds in high yield from hydroxy aromatic compounds and a method of preparing intermediates thereof. The hydroxy aromatic compound can be a mono-, bi- or tricyclic aromatic in which the rings are separate or fused. One or more of the rings can contain heteroatoms, such as oxygen, nitrogen, or sulfur, and can contain one or more substitutions, in addition to the hydroxy substitution.
    Type: Grant
    Filed: July 17, 2002
    Date of Patent: February 4, 2003
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Gauri Sankar Lal, Kathryn Sue Hayes
  • Publication number: 20020198417
    Abstract: A method of preparing vicinal difluoro aromatic compounds in high yield from hydroxy aromatic compounds and a method of preparing intermediates thereof. The hydroxy aromatic compound can be a mono-, bi- or tricyclic aromatic in which the rings are separate or fused. One or more of the rings can contain heteroatoms, such as oxygen, nitrogen, or sulfur, and can contain one or more substitutions, in addition to the hydroxy substitution.
    Type: Application
    Filed: July 17, 2002
    Publication date: December 26, 2002
    Inventors: Gauri Sankar Lal, Kathryn Sue Hayes
  • Patent number: 6479645
    Abstract: A sulfurpentafluoride and substituted silyl ethyne compound that is useful as precursors for a variety of organic compounds are disclosed. At least one of the substituents on the silicon atom is hindered. Also disclosed are high-yielding processes for making the ethyne compound of the present invention.
    Type: Grant
    Filed: March 22, 2002
    Date of Patent: November 12, 2002
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Gauri Sankar Lal, Kristen Elaine Minnich
  • Patent number: 6462191
    Abstract: A process for deoxofluorinating a C2-hydroxyl group of a furanose, includes: (a) mixing the furanose and a deoxofluorinating agent in a solvent to form a reaction mixture, and (b) heating the reaction mixture to greater than about 50° C. The process provides deoxofluorinated products, such as 2-fluoro-arabinoses, in yields of at least 80% of theoretical.
    Type: Grant
    Filed: July 13, 2000
    Date of Patent: October 8, 2002
    Assignee: Air Products and Chemicals, Inc.
    Inventor: Gauri Sankar Lal
  • Patent number: 6455744
    Abstract: A method of preparing vicinal difluoro aromatic compounds in high yield from hydroxy aromatic compounds and a method of preparing intermediates thereof. The hydroxy aromatic compound can be a mono-, bi- or tricyclic aromatic in which the rings are separate or fused. One or more of the rings can contain heteroatoms, such as oxygen, nitrogen, or sulfur, and can contain one or more substitutions, in addition to the hydroxy substitution.
    Type: Grant
    Filed: November 6, 2001
    Date of Patent: September 24, 2002
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Gauri Sankar Lal, Kathryn Sue Hayes
  • Publication number: 20020099247
    Abstract: A method of preparing vicinal difluoro aromatic compounds in high yield from hydroxy aromatic compounds and a method of preparing intermediates thereof. The hydroxy aromatic compound can be a mono-, bi- or tricyclic aromatic in which the rings are separate or fused. One or more of the rings can contain heteroatoms, such as oxygen, nitrogen, or sulfur, and can contain one or more substitutions, in addition to the hydroxy substitution.
    Type: Application
    Filed: November 6, 2001
    Publication date: July 25, 2002
    Inventors: Gauri Sankar Lal, Kathryn Sue Hayes
  • Patent number: 6242645
    Abstract: Diaryl-, dialkoxyalkyl-, alkylalkoxyalkyl-, arylalkoxyalkyl- and cyclic aminosulfur trifluorides fluorinating agents are disclosed.
    Type: Grant
    Filed: March 23, 2000
    Date of Patent: June 5, 2001
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Gauri Sankar Lal, Guido Peter Pez, Reno Joseph Pesaresi, Jr., Robert George Syvret
  • Patent number: 6222064
    Abstract: A fluorination method of oxygen and halogen sites with diaryl-, dialkoxyalkyl-, alkylalkoxyalkyl-, arylalkoxyalkyl- and cyclic aminosulfur trifluorides fluorinating reagents is disclosed.
    Type: Grant
    Filed: January 14, 2000
    Date of Patent: April 24, 2001
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Gauri Sankar Lal, Guido Peter Pez
  • Patent number: 6207860
    Abstract: Diaryl-, dialkoxyalkyl-, alkylalkoxyalkyl-, arylalkoxyalkyl- and cyclic aminosulfur trifluorides fluorinating agents are disclosed.
    Type: Grant
    Filed: September 29, 1997
    Date of Patent: March 27, 2001
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Gauri Sankar Lal, Guido Peter Pez, Reno Joseph Pesaresi, Jr.
  • Patent number: 6096922
    Abstract: A process for synthesizing an aminosulfur trifluoride is provided. The process includes reacting a secondary amine with SF.sub.4 to produce the aminosulfur trifluoride product and a liquid amine-HF adduct. Substantially no solid amine-HF adduct is produced in the one-step reaction of the process. The reaction is conducted in a reaction solvent containing a tertiary amine. The process produces aminosulfur trifluorides, such as dialkyl, diaryl and arylalkyl aminosulfur trifluorides, in high yields.
    Type: Grant
    Filed: November 1, 1999
    Date of Patent: August 1, 2000
    Assignee: Air Products and Chemicals, Inc.
    Inventor: Gauri Sankar Lal
  • Patent number: 6080886
    Abstract: A fluorination method of oxygen and halogen sites with diaryl-, dialkoxyalkyl-, alkylalkoxyalkyl-, arylalkoxyalkyl- and cyclic aminosulfur trifluorides fluorinating reagents is disclosed.
    Type: Grant
    Filed: September 29, 1997
    Date of Patent: June 27, 2000
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Gauri Sankar Lal, Guido Peter Pez