title: Ynamide carbopalladation: a flexible route to mono-, bi- and tricyclic azacycles.
abstract: Bromoenynamides represent precursors to a diversity of azacycles by a cascade sequence of carbopalladation followed by cross-coupling/electrocyclization, or reduction processes. Full details of our investigations into intramolecular ynamide carbopalladation are disclosed, which include the first examples of carbopalladation/cross-coupling reactions using potassium organotrifluoroborate salts; and an understanding of factors influencing the success of these processes, including ring size, and the nature of the coupling partner. Additional mechanistic observations are reported, such as the isolation of triene intermediates for electrocyclization. A variety of hetero-Diels-Alder reactions using the product heterocycles are also described, which provide insight into Diels-Alder regioselectivity.
authors.affiliation: Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA (U.K.) edward.
authors.forename: Craig D
authors.initials: CD
authors.lastname: Campbell
authors.affiliation: Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA (U.K.) edward.
authors.forename: Rebecca L
authors.initials: RL
authors.lastname: Greenaway
authors.affiliation: Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA (U.K.) edward.
authors.forename: Oliver T
authors.initials: OT
authors.lastname: Holton
authors.affiliation: Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA (U.K.) edward.
authors.forename: P Ross
authors.initials: PR
authors.lastname: Walker
authors.affiliation: Syngenta Ltd. Jealott's Hill International Research Centre, Bracknell, Berkshire, RG42 6EY (U.K.).
authors.forename: Helen A
authors.initials: HA
authors.lastname: Chapman
authors.affiliation: Syngenta Ltd. Jealott's Hill International Research Centre, Bracknell, Berkshire, RG42 6EY (U.K.).
authors.forename: C Adam
authors.initials: CA
authors.lastname: Russell
authors.affiliation: AstraZeneca, Alderley Park, Macclesfield, SK10 4TF (U.K.).
authors.forename: Greg
authors.initials: G
authors.lastname: Carr
authors.affiliation: Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA (U.K.) edward.
authors.forename: Amber L
authors.initials: AL
authors.lastname: Thomson
authors.affiliation: Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA (U.K.) edward.. anderson@chem.ox.ac.uk.
authors.forename: Edward A
authors.initials: EA
authors.lastname: Anderson
keywords: Suzuki coupling; domino reactions; hetero-Diels-Alder reactions; palladium catalysis; ynamides