Patents by Inventor Stephane Frein

Stephane Frein 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).

  • Process for the preparation of 1,3,2-oxazaborolidine compounds
    Patent number: 7586015
    Abstract: A process is used for the preparation of 1,3,2-oxazaborolidine compounds. This process prepares compounds of formula (I) or (IA): in which: R1 is an alkyl or an aryl; and R2, R3, R4 and R5 are especially a hydrogen atom or an alkyl, wherein the following are reacted in two steps: a) a boric precursor compound with an acetal compound to give a boronate compound; and b) the boronate compound with an amino alcohol compound. This process avoids by-products and exhibits a very good stereospecificity.
    Type: Grant
    Filed: January 25, 2007
    Date of Patent: September 8, 2009
    Assignee: Zach System
    Inventors: Alain Burgos, Stëphane Frein
  • METHOD FOR THE SYNTHESIS OF 4-BENZOFURAN-CARBOXYLIC ACID
    Publication number: 20090131688
    Abstract: The invention concerns a novel method for synthesis of 4-benzofuran-carboxylic acid or alkyl ester thereof. This method is characterized in that a reaction for aromatization of a compound of formula (II) is performed for the synthesis of the compound of formula (I), according to the scheme A2 below: wherein R independently represents hydrogen or a linear or branched C1-15 alkyl group. With the invention, it is possible to industrially synthesize 4-benzofuran-carboxylic acid or alkyl ester thereof with good yield and very good purity.
    Type: Application
    Filed: February 25, 2008
    Publication date: May 21, 2009
    Applicant: ZACH SYSTEM
    Inventors: Alain Burgos, Martine Maruani, Florence Perrin, Stephane Frein
  • Process for the preparation of 1,3,2-oxazaborolidine compounds
    Publication number: 20080139851
    Abstract: A process is used for the preparation of 1,3,2-oxazaborolidine compounds. This process prepares compounds of formula (I) or (IA): in which: R1 is an alkyl or an aryl; and R2, R3, R4 and R5 are especially a hydrogen atom or an alkyl, wherein the following are reacted in two steps: a) a boric precursor compound with an acetal compound to give a boronate compound; and b) the boronate compound with an amino alcohol compound. This process avoids by-products and exhibits a very good stereospecificity.
    Type: Application
    Filed: January 25, 2007
    Publication date: June 12, 2008
    Applicant: PPG-SIPSY
    Inventors: Alain Burgos, Stephane Frein
  • Method for the in situ preparation of chiral compounds derived from oxazaborolidine-borane complexes which are used in asymmetric reduction reactions
    Patent number: 7365212
    Abstract: A process for the in situ preparation of chiral compounds derived from oxazaborolidine-borane complexes, wherein a metal borohydride, a Lewis base and an inorganic acid ester are brought together and an optically active amino alcohol and optionally a halide are then added. The compound obtained is a complex that is useful as a catalyst in asymmetric reduction reactions. The reaction is performed by adding the substance to be reduced, particularly prochiral ketones or ether oximes, in order to synthesize chiral alcohols or chiral amines.
    Type: Grant
    Filed: October 11, 2004
    Date of Patent: April 29, 2008
    Assignee: ZaCh System S.p.A.
    Inventors: Alain Burgos, Blandine Bertrand, Stéphane Frein, Jean-François Pluvie, Sonia Roussiasse
  • Method for the in situ preparation of chiral compounds derived from oxazaborolidine-borane complexes which are used in asymmetric reduction reactions
    Publication number: 20070055068
    Abstract: A process for the in situ preparation of chiral compounds derived from oxazaborolidine-borane complexes, wherein a metal borohydride, a Lewis base and an inorganic acid ester are brought together and an optically active amino alcohol and optionally a halide are then added. The compound obtained is a complex that is useful as a catalyst in asymmetric reduction reactions. The reaction is performed by adding the substance to be reduced, particularly prochiral ketones or ether oximes, in order to synthesize chiral alcohols or chiral amines.
    Type: Application
    Filed: October 11, 2004
    Publication date: March 8, 2007
    Applicant: PPG-sipsy
    Inventors: Alain Burgos, Blandine Bertrand, Stephane Frein, Jean-Francois Pluvie, Sonia Roussiasse