| Number | Date | Country | Kind |
|---|---|---|---|
| 3805758 | Feb 1988 | DEX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 2345237 | Chitwood et al. | Mar 1944 | |
| 4769457 | Helwig et al. | Sep 1988 |
| Number | Date | Country |
|---|---|---|
| 0213570 | Aug 1986 | EPX |
| 0272589 | Dec 1987 | EPX |
| 0272591 | Dec 1987 | EPX |
| 2300638 | Jan 1973 | DEX |
| 2291203 | Nov 1974 | FRX |
| 1399561 | Jul 1975 | GBX |
| 1408658 | Oct 1975 | GBX |
| Entry |
|---|
| Organic Synthesis Band 64, 1985, Seiten 27-38; S. H. Bertz et al.: "Condensation of Dimethyl 1-3-Acetone--Dicarboxylate with 1,2-Dicarbonyl Compounds: Cis-Bicyclo (3.3.0) Octane -3,7-Diones". |