Molybdenum-catalyzed stannylations as key steps in heterocyclic synthesis.
THF/carbonyl complexes of molybdenum and tungsten are suitable precursors for the synthesis of the corresponding monoisonitrile carbonyl complexes. Whereas complexes with electron-rich isonitriles are suitable for regioselective hydrostannations, complexes with electron-poor isonitriles are efficient catalysts for distannations, without reduction of aromatic halides. This allows for the synthesis of halogenated distannylated allyl ethers, which can be subjected to intramoleculare Stille couplings giving rise to heterocycles, which can be further modified at the remaining stannyl group.
Braune
Sascha
S
Institut für Organische Chemie, Universität des Saarlandes, D-66123 Saarbrücken, Germany.
Pohlman
Matthias
M
Kazmaier
Uli
U