Development of a second generation palladium-catalyzed cycloalkenylation and its application to bioactive natural product synthesis.

Development of a second generation palladium-catalyzed cycloalkenylation and its application to bioactive natural product synthesis.

Natural product communications (2013-08-29)

Masahiro Toyota

ABSTRACT

A novel palladium-catalyzed intramolecular oxidative alkylation of unactivated olefins is described. This protocol was devised to solve one of the drawbacks of the original palladium-catalyzed cycloalkenylation that we developed. We call this new procedure the 'second generation palladium-catalyzed cycloalkenylation'. This protocol has been applied to the total syntheses of cis-195A, trans-195A, boonein, scholareins A, C, D, and alpha-skytanthine.

MATERIALS

Product Number

Brand

Product Description

686468

Sigma-Aldrich

Palladium, nanopowder, <25 nm particle size (TEM), ≥99.5%

287474

Sigma-Aldrich

Palladium, foil, thickness 0.5 mm, 99.9% trace metals basis

464651

Sigma-Aldrich

Palladium, powder, <75 μm, 99.9% trace metals basis

203998

Sigma-Aldrich

Palladium, powder or granules, 99.99% trace metals basis

203939

Sigma-Aldrich

Palladium, powder, 99.995% trace metals basis

326666

Sigma-Aldrich

Palladium, powder, <1 μm, ≥99.9% trace metals basis

348678

Sigma-Aldrich

Palladium, foil, thickness 1.0 mm, 99.9% trace metals basis

348643

Sigma-Aldrich

Palladium, foil, thickness 0.25 mm, 99.98% trace metals basis

348694

Sigma-Aldrich

Palladium, wire, diam. 0.5 mm, 99.9% trace metals basis

267082

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Palladium, sponge, 99.9% trace metals basis

267112

Sigma-Aldrich

Palladium, wire, diam. 1.0 mm, 99.9% trace metals basis

267120

Sigma-Aldrich

Palladium, foil, thickness 0.025 mm, 99.9% trace metals basis

373206

Sigma-Aldrich

Palladium, evaporation slug, diam. × L 0.6 cm × 0.6 cm, 99.95% trace metals basis

GF60084424

Palladium, foil, light tested, 100x100mm, thickness 0.025mm, as rolled, 99.99+%

GF94632576

Palladium, foil, light tested, 100x100mm, thickness 0.075mm, as rolled, 99.95%

GF23374661

Palladium, foil, 8mm disks, thickness 0.50mm, as rolled, 99.95%

GF74894136

Palladium, foil, 8mm disks, thickness 0.25mm, as rolled, 99.95%

GF57528816

Palladium, foil, not light tested, 25x25mm, thickness 0.006mm, 99.95%

GF55245821

Palladium, foil, not light tested, 100x100mm, thickness 0.025mm, as rolled, 99.99+%

GF69074916

Palladium, foil, not light tested, 25x25mm, thickness 0.00075mm, permanent polyester support, 99.75%

GF55924241

Palladium, foil, not light tested, 25x25mm, thickness 0.025mm, as rolled, 99.99+%

GF90427866

Palladium, foil, light tested, 100x100mm, thickness 0.025mm, as rolled, 99.95%

GF44874995

Palladium, foil, light tested, 100x100mm, thickness 0.047mm, as rolled, 99.95%

GF71571270

Palladium, foil, 4mm disks, thickness 0.0125mm, 99.95%

GF50856352

Palladium, foil, 15mm disks, thickness 0.006mm, 99.95%

GF62571236

Palladium, foil, 50x50mm, thickness 0.1mm, as rolled, 99.99+%

GF71821212

Palladium, foil, 4mm disks, thickness 0.047mm, as rolled, 99.95%

GF50184558

Palladium, foil, 15mm disks, thickness 0.02mm, as rolled, 99.95%

GF40284503

Palladium, foil, 0.5m coil, thickness 0.1mm, coil width 2mm, as rolled, 99.95%

GF45928356

Palladium, foil, 25mm disks, thickness 0.025mm, as rolled, 99.99+%