title: Stereoselective Synthesis of Substituted Oxocene Cores by Lewis Acid Promoted Cyclization.
abstract: Substituted oxocene derivatives have been synthesized by Lewis acid catalyzed reactions of ε-hydroxyalkene and substituted aromatic aldehydes. The Cu(OTf)2-bis-phosphine catalyzed reaction typically provides substituted dihydropyran derivatives through an olefin migration followed by a Prins cyclization. The corresponding reaction catalyzed by TMSOTf or BF3·OEt2 provided eight-membered cyclic ethers (oxocenes), selectively. This methodology provides convenient access to a variety of 2,4,8-trisubstituted oxocenes in good yields and excellent diastereoselectivities.
authors.affiliation: Department of Chemistry and Department of Medicinal Chemistry, Purdue University , 560 Oval Drive, West Lafayette, Indiana 47907, United States.
authors.forename: Arun K
authors.initials: AK
authors.lastname: Ghosh
authors.affiliation: Department of Chemistry and Department of Medicinal Chemistry, Purdue University , 560 Oval Drive, West Lafayette, Indiana 47907, United States.
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Tomaine
authors.affiliation: Department of Chemistry and Department of Medicinal Chemistry, Purdue University , 560 Oval Drive, West Lafayette, Indiana 47907, United States.
authors.forename: Kelsey E
authors.initials: KE
authors.lastname: Cantwell
mesh_terms: D000447:Aldehydes / Q000737:chemistry; D000475:Alkenes / Q000737:chemistry; D001688:Biological Products / Q000737:chemistry; D002384:Catalysis; D003500:Cyclization; D058116:Lewis Acids / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D035964:Oxocins / Q000138:chemical synthesis* / Q000737:chemistry; D011714:Pyrans / Q000138:chemical synthesis; D013237:Stereoisomerism
chemical_list: D000447:Aldehydes; D000475:Alkenes; D001688:Biological Products; D058116:Lewis Acids; D035964:Oxocins; D011714:Pyrans
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