Patents by Inventor Thomas Raffel

Thomas Raffel 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).

  • Preparation of sec. or tert. alcohols
    Patent number: 5223633
    Abstract: A process for the preparation of a compound of the formula ##STR1## which comprises deprotonating a carbamate of the formula ##STR2## in an inert solvent with a selective base, in the presence of a chelate-forming diamine to give a compound of the formula ##STR3## and then reacting III in an inert solvent, either with an achiral electrophile of the formula (IV) or (V) or with an optionally prochiral electrophile of the formula (VI) ##STR4## and in the case in which R.sup.1 represents an electrofugic leaving group, optionally again electrophilically substituted with the formation of an acyl anion and renewed deprotonation, and in a last step, solvolytically removing the protecting group --CO--NR.sup.10 R.sup.11.
    Type: Grant
    Filed: February 19, 1992
    Date of Patent: June 29, 1993
    Assignee: Bayer Aktiengesellschaft
    Inventors: Dieter Hoppe, Petra Tebben, Folker Hintze, Thomas Raffel