Switchable Synthesis of <i>Z</i>
-Homoallylic Boronates and <i>E</i>
-Allylic Boronates by Enantioselective Copper-Catalyzed 1,6-Boration
作者:Yunfei Luo、Steven M. Wales、Stamatis E. Korkis、Iain D. Roy、William Lewis、Hon Wai Lam
DOI:10.1002/chem.201801804
日期:2018.6.12
The enantioselective Cu‐catalyzed 1,6‐boration of (E,E)‐α,β,γ,δ‐unsaturated ketones is described, which gives homoallylic boronates with high enantiomeric purity and unexpectedly high Z‐selectivity. By changing the solvent, the outcome can be altered to give E‐allylic boronates.
toward the total synthesis of iso-archazolids and archazologs are reported. Both a biomimetic and a multistep total synthesis of iso-archazolid B, the most potent and least abundant archazolid, are described. The bioinspired conversion from archazolid B was realized by a high-yielding 1,8-Diazabicyclo[5.4.0]undec-7-ene catalyzed one-step double-bond shift. A highly stereoselectivetotal synthesis was
A straightforward, two-step asymmetric synthesis of octahydroindoles has been developed on the basis of two complementary strategies: (i) an organocatalyzed Michael reaction followed by a tandem Robinson–aza-Michael double cyclization catalyzed by PS-BEMP, and (ii) a diastereoselective cyclization, which formally constitutes a remote 1,6 asymmetric induction mediated by PS-BEMP. This allowed the construction
wish to describe a concise, protecting‐group‐free total synthesis of cabucine oxindole A, a putative natural spirooxindole alkaloid and a possible biosynthetic congener of cabucine and palmirine. Key transformations of our approach include a one‐step, organocatalytic and enantioselective construction of the spiro[pyrrolidine‐3,3’‐oxindole] moiety and a Korte rearrangement to furnish the final dihydropyran
time, reported the enantioselective synthesis of strychnofoline proceeding in only nine steps from commercially available 6-methoxytryptamine. The efficiency of the synthesis derivesfrom the use of two sequential transformation steps in the catalytic asymmetric construction of the spiro[pyrrolidine-3,3′-oxindole] motif in a facile manner. Our route is amenable to the synthesis of other natural and synthetic