Patents by Inventor Donald F. Halpern

Donald F. Halpern 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: 5283372
    Abstract: A process for the preparation of highly purified optical isomers of desflurane, i.e. 2-(difluoromethoxy)-1,1,1,2-tetrafluoroethane, is described wherein the highly purified opposite optical isomer of iso-flurane is reacted with bromine trifluoride in the cold, preferably in the presence of a solvent. A preferred solvent is bromine. The highly purified positive isomer of desflurane is advantageous over the negative isomer or the racemate.
    Type: Grant
    Filed: April 15, 1993
    Date of Patent: February 1, 1994
    Assignee: Anaquest, Inc.
    Inventors: Leonid A. Rozov, Chialang Huang, Donald F. Halpern, Gerald G. Vernice
  • Patent number: 5015781
    Abstract: The present invention is directed to a method of preparing a compound 2-(difluoromethoxy)-1,1,1,2-tetrafluoroethane by reacting 2-(difluoromethoxy)-1,1,1-trifluoro-2-chloroethane with bromine trifluoride. This reaction product is useful for inducing and maintaining anesthesia in warm blooded animals.
    Type: Grant
    Filed: May 18, 1990
    Date of Patent: May 14, 1991
    Assignee: BOC, Inc.
    Inventors: Mark L. Robin, Donald F. Halpern
  • Patent number: 4996371
    Abstract: The present invention is directed to a method for replacing a carboxylic acid group with a fluorine group in a halogenated aliphatic carboxylic acid compound having the formula, R-COOH, to prepare a fluorinated product having the formula, R-F, wherein R is a halogenated aliphatic group including straight- and branched-chain aliphatic groups selected from the group consisting of halogenated aliphatic and alkoxy-substituted halogenated aliphatic groups, wherein the method comprises the steps of (a) reacting the halogenated aliphatic carboxylic acid compound with bromine trifluoride, and (b) recovering the fluorinated product.
    Type: Grant
    Filed: January 16, 1990
    Date of Patent: February 26, 1991
    Assignee: BOC, Inc.
    Inventors: Donald F. Halpern, Mark L. Robin
  • Patent number: 4972040
    Abstract: A process for the preparation of a compound having the formula CF.sub.3 CHFOCH.sub.3 comprising reacting a fluorinating agent with the reaction product of CF.sub.3 CH(OH)OCH.sub.3 and p-toluene sulfonyl chloride and an improved method for the preparation of CHF.sub.2 OCHFCF.sub.3 through the use of such compounds.
    Type: Grant
    Filed: July 17, 1989
    Date of Patent: November 20, 1990
    Assignee: BOC, Inc.
    Inventors: Mark L. Robin, Donald F. Halpern
  • Patent number: 4888139
    Abstract: Process for preparing CHF.sub.2 OCHFCF.sub.3 through the use of novel intermediate compounds CHCl.sub.2 OCH.sub.2 COCl and CHCl.sub.2 OCHClCOCl.
    Type: Grant
    Filed: January 25, 1989
    Date of Patent: December 19, 1989
    Assignee: BOC, Inc.
    Inventors: Donald F. Halpern, Mark L. Robin
  • Patent number: 4874901
    Abstract: Sodium or potassium fluoride has been found to efficiently fluorinate the chloro atom adjacent the ether oxygen in chloro-fluoro organic ethers. The reaction proceeds efficiently without added solvent at an elevated temperature and pressure.
    Type: Grant
    Filed: May 6, 1988
    Date of Patent: October 17, 1989
    Assignee: BOC, Inc.
    Inventors: Donald F. Halpern, Mark L. Robin
  • Patent number: 4855511
    Abstract: Process for preparing CHF.sub.2 OCHFCF.sub.3 through the use of novel intermediate compounds CHCl.sub.2 OCH.sub.2 COCl and CHCl.sub.2 OCHClCOCl.
    Type: Grant
    Filed: July 18, 1988
    Date of Patent: August 8, 1989
    Assignee: BOC, Inc.
    Inventors: Donald F. Halpern, Mark L. Robin
  • Patent number: 4098577
    Abstract: A system for indicating the integrity of a normally sealed package utilizes a sensor containing a pH sensitive dye which displays a first color in equilibrium with normal atmospheric conditions and a second color when in equilibrium with an artificial atmosphere comprising an acidic gaseous material. When the air normally in the package is displaced by the artificial atmosphere, the pH sensitive dye assumes its second color. Loss of integrity of the sealed package results in loss of the acidic gaseous material. As a consequence, the pH sensitive dye reverts to its first color, thereby signaling the loss of package integrity.
    Type: Grant
    Filed: May 27, 1975
    Date of Patent: July 4, 1978
    Assignee: Bio-Medical Sciences Inc.
    Inventor: Donald F. Halpern
  • Patent number: RE35568
    Abstract: The present invention is directed to a method for replacing a carboxylic acid group with a fluorine .[.group.]. in a halogenated aliphatic carboxylic acid compound having the formula, R-COOH, to prepare a fluorinated product having the formula, R-F, wherein R is a halogenated aliphatic group including straight- and branched-chain aliphatic groups selected from the group consisting of halogenated aliphatic and .Iadd.halogenated .Iaddend.alkoxy-substituted .[.halogenated.]. aliphatic groups, wherein the method comprises the step of (a) reacting the halogenated aliphatic carboxylic acid compound with bromine trifluoride, and (b) recovering the fluorinated product.
    Type: Grant
    Filed: November 16, 1994
    Date of Patent: July 22, 1997
    Assignee: Ohmeda Pharmaceutical Products Division Inc.
    Inventors: Donald F. Halpern, Mark L. Robin