Only two oxygen atoms, at C-13 and C-5, remained to be installed to complete the synthesis. Both oxidations could be achieved in a single step by treating the crude silyl enol ether of 19 with DMDO to afford a nitrone 20 (73% overall yield). Subsequent heating of 20 in the presence of Ac2O and TEA presumably triggers a Boekelheide type rearrangement to deliver a diacetate (compound 39, see the SI) as a single diastereomer, followed by regioselective hydrolysis of the C-5 acetate using LiOH to yield monoacetate 21 (64%) on 330-mg scale. At this point, the vinyl triflate which had remained a silent observer throughout the synthesis was now called upon to append the final two carbon atoms of 1 and 2. Thus, a Suzuki coupling was chosen to install the exocyclic vinyl group, delivering diene 22 in 75% yield. To complete the synthesis, 22 was oxidized with DMP, followed by hydrolysis, affording portimine B (PB, 2) in 88% yield. During these studies we suspected that the originally assigned structure of 2 as a ring-opened tautomer was incorrect and this was now confirmed to be the same ring-closed tautomer expressed in 1. To complete the synthesis of portimine A (PA, 1), crude 2 in methanol could be stereoselectively reduced by NaBH3CN in high isolated yield (80%).