Practical asymmetric approach to medium-sized carbocycles based on the combination of two ru-catalyzed transformations and a lewis Acid-induced cyclization.
[Reaction: see text] Ruthenium-catalyzed coupling of allyl ethyl ether to optically active 1-trimethylsilyl-1-alkyn-3-ols, followed by in situ ketalization and Lewis-acid-induced cyclization, affords enantiomerically pure 1,5-oxygen-bridged eight- and nine-membered carbocycles. Opening of the oxygen bridge under basic or electron transfer conditions provides optically pure medium-sized carbocycles, products that are difficult to construct using other currently available methodologies.
López
Fernando
F
Departamento de Química Orgánica y Unidad Asociada al CSIC, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
Castedo
Luis
L
Mascareñas
José L
JL
D000143:Acids / Q000737:chemistry*; D000475:Alkenes / Q000737:chemistry; D000480:Alkynes / Q000737:chemistry; D000838:Anions; D002384:Catalysis; D002412:Cations; D003500:Cyclization; D004987:Ethers / Q000737:chemistry; D047028:Macrocyclic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D012428:Ruthenium / Q000737:chemistry*; D013237:Stereoisomerism
D000143:Acids; D000475:Alkenes; D000480:Alkynes; D000838:Anions; D002412:Cations; D004987:Ethers; D047028:Macrocyclic Compounds; D012428:Ruthenium