A Unified Synthetic Strategy to the Cryptocarya Family of Natural Products Exploiting Anion Relay Chemistry (ARC)

A unified synthetic strategy to the Cryptocarya family of natural products has been achieved employing four-component fragment unions in a “single flask” exploiting Anion Relay Chemistry (ARC). Functionalization of the ARC adducts permits rapid construction of five polyhydroxylated di- and tetrahydropyrone natural products of the Cryptocarya class (<b>1</b>–<b>5</b>), in a total of 7–9 steps from commercially available materials

Polymer-Supported Siloxane Transfer Agents for Pd-Catalyzed Cross-Coupling Reactions

The design, synthesis, and validation of a ring-opening metathesis polymerization (ROMP) polymer supporting siloxane transfer agents have been achieved that permit efficient palladium-catalyzed cross-coupling reactions. The solubility properties of the polymer facilitate not only product purification but also polymer recycling without significant loss of cross-coupling activity

The Daphniphyllum Alkaloids: Total Synthesis of (−)-Calyciphylline N

Presented here is a full account on the development of a strategy culminating in the first total synthesis of the architecturally complex daphni­phyllum alkaloid, (−)-calyci­phylline N. Highlights of the approach include a highly diastereo­selective, intra­molecular Diels–Alder reaction of a silicon-tethered acrylate; an efficient Stille carbonyl­ation of a sterically encumbered vinyl triflate; a one-pot Nazarov cyclization/​proto-desilyl­ation sequence; and the chemo­selective hydrogenation of a fully substituted diene ester

Total Synthesis of (−)-Calyciphylline N

The total synthesis of the architecturally complex <i>Daphni­phyllum</i> alkaloid (−)-calyci­phylline N has been achieved. Highlights of the synthesis include a Et₂AlCl-promoted, highly stereo­selective, susbtrate-controlled intramolecular Diels–Alder reaction, a transannular enolate alkylation, an effective Stille carbonylation/Nazarov cyclization sequence, and a high-risk diastereo­selective hydrogen­ation of a fully substituted conjugated diene ester

The Daphniphyllum Alkaloids: Total Synthesis of (−)-Calyciphylline N

Presented here is a full account on the development of a strategy culminating in the first total synthesis of the architecturally complex daphni­phyllum alkaloid, (−)-calyci­phylline N. Highlights of the approach include a highly diastereo­selective, intra­molecular Diels–Alder reaction of a silicon-tethered acrylate; an efficient Stille carbonyl­ation of a sterically encumbered vinyl triflate; a one-pot Nazarov cyclization/​proto-desilyl­ation sequence; and the chemo­selective hydrogenation of a fully substituted diene ester

Total Synthesis of (−)-Secu’amamine A Exploiting Type II Anion Relay Chemistry

A total synthesis of (−)-secu’amamine A has been achieved exploiting Type II Anion Relay Chemistry (ARC) to provide the full linear carbon and nitrogen skeleton in a single flask with the requisite stereochemistry and functionality. A mechanistic rationale is also proposed to account for the stereochemical outcome of the key aldol reaction leading to the advanced aza tricyclic core

Validation of Diethoxyphosphonate as an Effective Agent for Charge Transfer in Anion Relay Chemistry (ARC)

The diethoxyphosphonate group comprises an effective agent to achieve negative charge migration in Type II Anion Relay Chemistry (ARC). The process involves a [1,4]-phosphorus-Brook rearrangement that proceeds via a phosphacyclic intermediate leading to an anion that can be captured by reactive electrophiles. In the absence of an exogenous electrophile, the anion derived via phosphorus migration undergoes internal displacement of the phosphonate group to produce a diastereomeric mixture of cyclopropanes

Total Synthesis of (+)-18-<i>epi-</i>Latrunculol A

An enantioselective total synthesis of the cytotoxic latrunculin congener (+)-18-<i>epi</i>-latrunculol A has been achieved. Key steps in the synthetic route include an acid-mediated enone cyclization/equilibration sequence, a Carreira alkynylation, and a late-stage Mitsunobu macrolactonization to construct the macrolide skeleton

Total Synthesis of (+)-18-<i>epi</i>-Latrunculol A: Development of a Synthetic Route

The evolution of an enantioselective total synthesis of (+)-18-<i>epi</i>-latrunculol A, a congener of the marine-sponge-derived latrunculins A and B, is reported. Key steps include a late-stage Mitsunobu macrolactonization to construct the 16-membered macrolactone, a mild Carreira alkynylation to unite the northern and southern hemispheres, a diastereoselective, acid-mediated δ-hydroxy enone cyclization/equilibration sequence, and a functional-group-tolerant cross-metathesis to access the enone cyclization precursor

Total Synthesis of (+)-18-<i>epi-</i>Latrunculol A

An enantioselective total synthesis of the cytotoxic latrunculin congener (+)-18-<i>epi</i>-latrunculol A has been achieved. Key steps in the synthetic route include an acid-mediated enone cyclization/equilibration sequence, a Carreira alkynylation, and a late-stage Mitsunobu macrolactonization to construct the macrolide skeleton