Appeal No. 2000-0344
Application No. 08/718,408
“The oxidation of ? -5-steroidal alkenes to the corresponding enones is an
important step in the synthesis of steroid end-products useful as 5a-reductase
inhibitors. Chromium based oxidations have previously been used for the
oxidation of allylic groups, but are environmentally unacceptable and require
silica gel chromatography. The instant invention provides an improved
alternative method for oxidizing ? -5-steroidal alkenes.” Id., pages 1-2.
“Particularly, this invention involves conversion of ? -5-steroidal alkenes to ? -5-7-
keto-steroidal alkenes using a ruthenium based catalyst in the presence of a
hydroperoxide.” Id., page 2.
Discussion
The examiner rejected all of the claims as obvious over the disclosure of
either Pearson or Muzart, combined with Neumann. The examiner characterizes
Pearson as teaching
a process for the allylic oxidation of a variety of alkenes using t-
butyl hydroperoxide in the presence of a chromium -based catalyst.
. . . The reference specially teaches the oxidation of 5-ene steroids
and the production of 5-ene-7-one steroids.
Examiner’s Answer, page 4. The examiner cites Muzart as teaching exactly the
same thing. See the Examiner’s Answer, page 5.
The examiner acknowledges that Pearson and Muzart do not use a
ruthenium-based catalyst, as recited in the instant claims. Neumann is cited to
make up this difference. The examiner states that Neumann teaches “oxidation
of alkenes using different oxidants including t-butyl hydroperoxide in the
presence of a ruthenium based catalyst.” The examiner concluded that it would
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