Asymmetrization of a Meso 1,2-Enediol Bis(trimethylsilyl) Ether Using a (S)-BINOL Monoisopropyl Ether(BINOL-Pri)-Tin Tetrachloride Complex: An Alternative Route to (−)-Ketodicyclopentadiene and (−)-Ketotricyclononene

✍ Scribed by Takahiko Taniguchi; Kunio Ogasawara

• Publisher: Elsevier Science
• Year: 1997
• Tongue: French
• Weight: 521 KB
• Volume: 38
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(97)01488-3

✦ Synopsis

A tticyclic meso 1,2-enediol bis(trimethylsilyl) ether having an endotricyclo[4.2. 1.02s]nonenefmmework has beenasymmetrically desyrnmetrized by protonationwith a complexgenerated bm (S)-BINOLmonoisopropyl ether(BINOL-W)andtin tetmachloride to give the opticallyenrichedacyloinin 90%ee. Thechirafscylointhusobtainedhas been transformed into two versatilechid buildingblocks,(-)-ketodicyclopentadiene and(-)-ketooicyclononene, in opticallypute formsvia a sequenceinvolvingconcurrent enzymaticacetylation andopticalpurification. 0 1997ElsevierScienceLtd.