title: Further studies of intramolecular Michael reactions of nitrosoalkenes for construction of functionalized bridged ring systems.
abstract: A wide variety of stabilized carbanions have been found to participate as nucleophiles in intramolecular Michael-type conjugate additions to in situ generated nitrosoalkenes to form bridged carbocyclic systems. The vinylnitroso platforms for these cyclizations have been prepared via two key steps involving ring-closing metathesis of vinyl chlorides and regioselective conversion of vinyl chlorides to α-chloroketones with sodium hypochlorite in glacial acetic acid/acetone. An alternative approach to preparation of some cyclization substrates has involved use of more reactive enol ethers as precursors to the requisite α-chloroketones. A sulfonamide anion has also been found to be an effective nucleophile in this type of reaction, leading to formation of a 6-azabicyclo[3.2.1]octane.
authors.affiliation: Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: Praveen
authors.initials: P
authors.lastname: Kumar
authors.forename: Puhui
authors.initials: P
authors.lastname: Li
authors.forename: Ilia
authors.initials: I
authors.lastname: Korboukh
authors.forename: Tony L
authors.initials: TL
authors.lastname: Wang
authors.forename: Hemant
authors.initials: H
authors.lastname: Yennawar
authors.forename: Steven M
authors.initials: SM
authors.lastname: Weinreb
mesh_terms: D000838:Anions / Q000737:chemistry*; D053961:Azabicyclo Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D001952:Bridged-Ring Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D003500:Cyclization; D003516:Cycloparaffins / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009603:Nitroso Compounds / Q000737:chemistry*; D013237:Stereoisomerism; D013449:Sulfonamides / Q000737:chemistry*
chemical_list: C561068:6-azabicyclo(3.2.1)octane; D000838:Anions; D053961:Azabicyclo Compounds; D001952:Bridged-Ring Compounds; D003516:Cycloparaffins; D009603:Nitroso Compounds; D013449:Sulfonamides