Appeal No. 1996-3017 Application No. 08/851,810 ordinary skill in the art would have had a reasonable expectation of successfully isolating the product alkyl- pyrazine from the aqueous medium utilizing the recrystallization method disclosed by Bonzom. Appellant has not apprised us of any reason, and we are not aware of one, why one of ordinary skill in the art would have been dissuaded from applying Bonzom's recrystallization technique to an aqueous medium comprising an alkyl-pyrazine simply because the reactant mixture may contain amounts of an acetylene starting reactant rather than an acyloin starting reactant. Also, since distillation, extraction and recrystallization are all conventional techniques used in the art to isolate compounds from aqueous medium, we are satisfied that one of ordinary skill in the art would have found it obvious to simply determine which of the known techniques produce the optimum yield without the need to resort to undue experimentation. Compare In re Boesch, 617 F.2d 272, 276, 205 USPQ 215, 219 (CCPA 1980). We find no flaw in the following reasoning of the examiner: The different modes of purification would be considered alternately and even sequentially usable since isolation is a separate consideration for the synthetic chemist once a product mixture is obtained -6-Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 NextLast modified: November 3, 2007