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%

GF90203475

Palladium, foil, not light tested, 25x25mm, thickness 0.0025mm, 99.95%

GF15900713

Palladium, microfoil, disks, 25mm, thinness 0.5μm, specific density 303.4μg/cm², permanent mylar 3.5μm support, 99.99%

GF89451489

Palladium, rod, 50mm, diameter 2.0mm, 99.95%

GF21222447

Palladium, foil, not light tested, 50x50mm, thickness 0.02mm, as rolled, 99.95%

GF99402510

Palladium, microfoil, disks, 50mm, thinness 0.05μm, specific density 63.6μg/cm², permanent mylar 3.5μm support, 99.99%

GF01313761

Palladium, foil, not light tested, 50x50mm, thickness 0.002mm, 99.95%

203939

Sigma-Aldrich

Palladium, powder, 99.995% trace metals basis

373206

Sigma-Aldrich

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

203998

Sigma-Aldrich

Palladium, powder or granules, 99.99% trace metals basis

464651

Sigma-Aldrich

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

348694

Sigma-Aldrich

Palladium, wire, diam. 0.5 mm, 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

267082

Sigma-Aldrich

Palladium, sponge, 99.9% trace metals basis

267120

Sigma-Aldrich

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

267112

Sigma-Aldrich

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

326666

Sigma-Aldrich

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

287474

Sigma-Aldrich

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

GF90427866

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

GF23374661

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

GF35196330

Palladium, tube, 100mm, outside diameter 2.0mm, inside diameter 1.6mm, wall thickness 0.2mm, as drawn, 99.95%

GF43081174

Palladium, foil, not light tested, 100x100mm, thickness 0.0125mm, 99.95%

GF52273852

Palladium, wire reel, 10m, diameter 0.025mm, as drawn, 99.9%

GF03781863

Palladium, foil, light tested, 25x25mm, thickness 0.025mm, as rolled, 99.95%

GF59343688

Palladium, foil, not light tested, 50x50mm, thickness 0.0125mm, 99.95%

GF96367977

Palladium, foil, not light tested, 25x25mm, thickness 0.001mm, permanent polyester support, 99.75%

GF99300371

Palladium, wire reel, 50m, diameter 0.125mm, hard, 99.95%

GF47015793

Palladium, wire reel, 10m, diameter 0.05mm, as drawn, 99.9%

GF88212898

Palladium, foil, not light tested, 50x50mm, thickness 0.025mm, as rolled, 99.95%