Toward the Synthesis of Reidispongiolide A: An Improved Stereocontrolled Synthesis of the C23-C35 Fragment of Reidispongiolide A

An improved synthesis of the C23-C35 moiety of reidispongiolide A has been completed. An intermolecular Nozaki-Hiyama-Kishi coupling was employed for the union of C23-C30 and C31-C35 fragments. A discussion on the factors influencing the stereochemical outcome of (E)-crotylboration reactions of α-methyl-βl-alkoxy aldehydes is also presented.