Basenkatalysierte Cyclisierungen von 2-(2-Propinyl)oxybenzamiden
✍ Scribed by Veronica Scherrer; Martha Jackson-Mülly; Janos Zsindely; Hans Schmid
- Publisher
- John Wiley and Sons
- Year
- 1978
- Tongue
- German
- Weight
- 937 KB
- Volume
- 61
- Category
- Article
- ISSN
- 0018-019X
No coin nor oath required. For personal study only.
✦ Synopsis
Base Catalysed Cyclizations of 2‐(2‐Propynyl)oxy‐benzamide Systems
2‐(2‐Propynyl)oxy‐benzamides were cyclized under base catalysis to 6‐ or 7‐membered ring compounds, depending on the reaction conditions. Treatment of 2‐(2‐propynyl)oxy‐benzamide (10) with sodium methylsulfinylmethanide (NaMSM) in DMSO gave two isomeric oxazepinons 11 (34%) and 12 (7%), while the transformation with sodium‐2‐propanolate in 2‐propanol afforded the oxazinone 13 (34%) and with lithium cyclohexyl‐isopropylamide (Li‐CHIP) in N‐methylpyrrolidone 11 (48%) exclusively (Scheme 4). N‐Methyl‐2‐(2‐propynyl)‐oxy‐benzamide (14) behaved similarly. In the reaction of 14 with sodium 2‐propanolate in 2‐propanol yielding the benzoxazinone 16, the allenyloxy‐benzamide 17 could be isolated as an intermediate (Scheme 5). The N‐phenyl‐compounds 18 and 22 treated with NaMSM/DMSO were converted to 3‐anilino‐2‐methyl‐benzo‐ and naphtho‐pyran‐4‐ones, respectively (Schemes 6 and 7). The mechanisms for these reactions are discussed (Schemes 8, 9 and 10).
📜 SIMILAR VOLUMES
Im folgenden werden nach einem Vorscblag von u. Auwers [l] die Bezeichnungen 0-undp-Semibenzol fur h-Alkyliden-l,3-cyclohexadiene bzw. 6-Alkyliden-1,4-cyclohexadiene verwendet. Teil der Dissertation von J. L., Universitat Zurich 1979.
Flow thermolysis of 2‐propynyl propiolate **(5)** at 580° afforded butatriene **(6)** (__ca.__ 50%) and, as by‐products, 4‐methylene‐2‐cyclobuten‐1‐one **(7)**, 2‐ethynylpropenal **(8)**, 1‐penten‐4‐yn‐3‐one **(9)**, 4‐penten‐2‐ynal **(10)** (total __ca.__ 10%), along with some propynal, acetylene,
Reductive Cyclizations of Ketyls of Bicyclo[2.2.2]octanones Depending on the reaction conditions the ketyls 2a/b of bicyclo[2.2.2]octanones 1a/b cyclize to the alcohols 3a/b and 4a/b, respectively.
## Abstract Durch basenkatalysierte Umwandlung entstehen aus 3‐Benzhydryliden‐2‐phenyl‐ und 3‐Benz‐ hydryliden‐2‐methyl‐1‐pyrrolin (**1b** bzw. **1c** ) die isomeren Pyrrolderivate **3b** bzw. **3c**. Während diese Reaktion bei Raumtemperatur schnell abläuft, wird bei −70°C aus **1c** das mesomere