Intramolecular Capture of HDDA-Derived Benzynes: (i) 6- to 12-Membered Ring Formation, (ii) Internally (vis-à-vis Remotely) Tethered Traps, and (iii) Role of the Rate of Trapping by the Benzynophile
作者:Yuanxian Wang、Thomas R. Hoye
DOI:10.1021/acs.orglett.7b03436
日期:2018.1.5
hexadehydro-Diels–Alder reaction of substrates containing tethered trapping moieties. Products having new structural motifs can be created. (i) Medium-sized fused rings can be produced by varying the length of the tether. (ii) The tether can emanate from an atom within the linker unit that joins the 1,3-diyne and diynophile. (iii) The importance of the rate of trapping by the benzynophile is established.
Gold(I)-Catalyzed Intramolecular [4+3]-Cycloaddition Reactions with Furan Propargyl Esters as the Substrates: Carbenoid vs. Stabilized Allyl Cation
作者:Benjamin Gung、Ryan Conyers、Josh Wonser
DOI:10.1055/s-0033-1338946
日期:——
The tricyclic ring system with an oxabicyclo[3.2.1]octadiene and a fused six-membered ring was produced efficiently using the readily available propargyl esterfuran substrate in the presence of a Au(I) complex. The reaction involves a tandem 3,3-rearrangement of the propargyl ester followed by an intramolecular [4+3]-cycloaddition reaction. Both the primary ligand of the gold complex (N-heterocyclic
Amino Acid Derived Enamides: Synthesis and Aminopeptidase Activity
作者:Richard R. Cesati、Greg Dwyer、Reinaldo C. Jones、Megan P. Hayes、Padmaja Yalamanchili、David S. Casebier
DOI:10.1021/ol7025729
日期:2007.12.1
Recently developed copper-catalyzed coupling methodology has been applied to the Synthesis of amino acid derived enamides. Bond formation proved to be strongly influenced by protection strategy and vinyl iodide substitution while tolerant of limited side chain functionality. Assessment of aminopeptidase activity revealed a preference for (E)-1,2-disubstituted constructs.