| 摘要 |
<p>PCT No. PCT/DE88/00011 Sec. 371 Date Jul. 24, 1989 Sec. 102(e) Date Jul. 24, 1989 PCT Filed Jan. 7, 1988 PCT Pub. No. WO88/05429 PCT Pub. Date Jul. 28, 1988.The invention relates to a process for the production of D,L-bicyclo[3.3.0]octane-3,7-dione-2-carboxylic acid esters of Formula I <IMAGE> (I) wherein R is methyl or ethyl, and Z isoxygen or the ketal residue <IMAGE> wherein X means ethylene, trimethylene or 2,2-dimethyltrimethylene, characterized in that D,L-bicyclo[3.3.0]octane-3,7-dione-2,6-dicarboxylic acid esters of Formula II <IMAGE> (II) wherein R has the meanings given above, are partially saponified and decarboxylated in an aqueous or water-containing medium in the presence of acids, and are optionally selectively ketalized.</p> |
