“…In order to eradicate the competing dehydration pathway (and, hence, formation of TsNH2), the possibility of effecting olefination of the aldehyde functionality prior to isocyanate trapping and cyclic carbamate formation was considered. Although reaction of 11 with Ph3P=CH(CH2)3OBn has already been shown to result in olefination and epoxide formation (undesired in this case), 14 and 20 but also that the formal substitution of the iodide functionality by an amino func-tionality had proceeded with inversion of configuration, as required for the synthesis of pseudodistomin E. With this transformation (i.e., 7 to 19) established, an end-game for the elaboration of lactone 7 into pseudodistomin E using the decarboxylative coupling of a carboxylic acid and a dialkylzinc reagent, recently reported by Baran et al, 23 E,8'Z):(6'Z,8'E):(Z,Z) ratio], the oxazolidinone moiety within 31 was cleaved using KOH in hot MeOH to give 32, and finally the N-Boc group was removed from 32 using HCl in hot MeOH to give synthetic pseudodistomin E 33 in 72% yield (from 31) and 82:8:8:2 dr [(E,E):(6'E,8'Z):(6'Z,8'E):(Z,Z) ratio]. The integrity of the diene geometry is clearly somewhat compromised during the coupling reaction, but the deprotection steps occur without further isomerization.…”