title: Selective cross-couplings. Sequential Stille-Liebeskind/Srogl reactions of 3-chloro-4-arylthiocyclobutene-1,2-dione.
abstract: The synthesis and initial reactivity studies of 2 are described. It was found that it participates in Stille couplings exclusively at the C-Cl site with a number of organostannanes (58-71% yield) in the absence of Cu(I). Then, these new derivatives were functionalized at the C-S site with boronic acids by switching to the Liebeskind-Srogl reaction conditions (in the presence of a Cu(I) carboxylate) to yield the bifunctionalized cyclobutenediones (44-90% yield).
authors.affiliation: Facultad de Química, Universidad de Guanajuato, Col. Noria Alta S/N, Guanajuato, Gto, 36050 Mexico.
authors.forename: Angélica
authors.initials: A
authors.lastname: Aguilar-Aguilar
authors.forename: Eduardo
authors.initials: E
authors.lastname: Peña-Cabrera