Experimental: How to Make Crabby Patties

To a flask flushed with N2 of the Grubbs containing catalyst (0.100 g, 0.12 mmol, 0.2 equiv) was added a solution compound 2 (0.220 g, 0.6 mmol) in dichloromethane (DCM) via syringe at room temperature. The resultant mixture was stirred under reflux for 6 hours. Then, a vacuum was used to filter the product, and the crude residual product was purified by flash column chromatography on silica gel using a 8:1 ratio of hexane:ethyl acetate. Compound 13 should be a colorless crystal.

A tube was first degassed with N2 before compound 13 (0.050 g, 0.15 mmol, 1.0 equiv.) was dissolved in ethanol (3 mL) and DCM (0.5 mL) to produce a solution in sealed tube. To this solution was added RhCl3 •3H2O, heated to 100 °C for 5 hours. It has also been proposed that heating the solution 100 °C for 3 hours under an atmosphere of Nitrogen is also able to cause the rhodium catalyzed double bond migration3 . Rhodium catalyzed alkene isomerization reactions  have been able to achieve high yield with only being heated for 1.5 hours3 . The solution was then cooled back to room temperature before the solvent was removed under vacuum filtration. The crude residual product was purified by flash column chromatography on silica gel using a 6:1 ratio of hexane:ethyl acetate to give pavidolide (1), a colorless crystal.

Pavidolide B (1): Rf = 0.40 (silica gel, hexane/EtOAc = 2:1, UV); [α]D = -146 (c = 0.42, MeOH); mp :