Patents by Inventor Felix Previdoli

Felix Previdoli 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: 4956473
    Abstract: 2-Aza-4-(alkoxycarbonyl)spiro[4,5]-decan-3-one and a process for the production of it, starting either from cyclohexylidene malonic acid esters or cyclohexylidene cyanoalkylates. The cyclohexylidene malonic acid ester is reacted with hydrocyanic acid in the presence of a catalytic amount of alkali cyanide or with a stoichiometric amount of alkali cyanide, in an alcohol, and subsequently treated with an acid. The resultant (1-cyanocyclohexyl) malonic acid dialkyl ester is converted by catalytic hydrogenation into the product. The cyclohexylidene cyanoalkylate is reacted with a stoichiometric amount of alkali cyanide, in an alcohol or with hydrocyanic acid in the presence of a catalytic amount of an alkali cyanide. The resultant (1-cyanocyclohexyl)-cyanoacetic acid alkyl ester is reacted in an alcohol in an acid to provide (1-cyanocyclohexyl) malonic acid dialkyl ester. The later ester is converted by catalytic hydrogenation into the product.
    Type: Grant
    Filed: August 30, 1989
    Date of Patent: September 11, 1990
    Assignee: Lonza Ltd.
    Inventors: Hans P. Mettler, Gareth Griffiths, Lester Mills, Felix Previdoli
  • Patent number: 4545934
    Abstract: Process for the production of 4-substituted acetoacetic acid derivatives. An acetoacetic acid derivative having the formula: ##STR1## wherein R is alkoxy having 1 to 6 C atoms, phenoxy, --NR'.sub.2, wherein R' is alkyl having 1 to 6 C atoms or aryl, or NR'.sub.2, which is azetidine, pyrrolidine or piperidine, is treated with a secondary amine at an elevated temperature and in the presence of an organic solvent. The water formed is separated. The intermediate is converted into the corresponding 3-enamine carboxylic acid derivative. The derivative is converted by treatment with sodium amide in liquid ammonia into the corresponding sodium salt. The sodium salt is converted by treatment with a halogen compound having the formula R.sub.1 CH.sub.2 X or R.sub.1 R.sub.2 CHX, wherein R.sub.1 and R.sub.2 each are alkyl, alkenyl, alkinyl or aryl and X is chlorine, bromine or iodide, into the corresponding 4-substituted enamino derivative. The derivative is hydrolyzed into the 4-substituted acetoacetic acid derivative.
    Type: Grant
    Filed: March 21, 1984
    Date of Patent: October 8, 1985
    Assignee: Lonza Ltd.
    Inventors: Felix Previdoli, Leander Tenud