Noteworthy observations accompanying synthesis of the apoptolidin disaccharide

A stereoselective synthesis of the apoptolidin disaccharide is reported. The key chemistry features a new transformation utilizing a highly selective tetramethylalkoxyalanate[V]-directed syn-methylation of a vinylogous ester, isolation of a hydrate of a 2-keto sugar, an eco-friendly radical cleavage of a bromomethyl group, and an efficient preparation of a fluorodisaccharide via the use of XtalFluor-E.