Palladium-catalyzed cross-coupling of terminal alkynes with 4-trifloyloxazole: studies toward the construction of the C26-C31 subunit of phorboxazole A.
[reaction: see text] A strategy has been developed that successfully takes advantage of transition-metal-catalyzed coupling reactions for the synthesis of highly functionalized oxazoles. Trifloyloxazoles have been used as coupling partners with alkyne-derived vinylmetallic intermediates in Stille- and Negishi-type couplings to assemble the corresponding oxazoles in good isolated yield. The results obtained provide a close analogy and thus good precedent to employ this strategy in the synthesis of the oxazole subunits of phorboxazole A.
Schaus
J V
JV
Department of Chemistry, Metcalf Center for Science and Engineering, Boston University, Massachusetts 02215, USA.
Panek
J S
JS
D000480:Alkynes / Q000737:chemistry*; D002384:Catalysis; D006576:Heterocyclic Compounds, 4 or More Rings / Q000737:chemistry*; D008698:Mesylates / Q000737:chemistry*; D010080:Oxazoles / Q000737:chemistry*; D010165:Palladium / Q000737:chemistry*
C408888:2-phenyl-4-trifloyloxazole; D000480:Alkynes; D006576:Heterocyclic Compounds, 4 or More Rings; D008698:Mesylates; D010080:Oxazoles; C408887:phorboxazole A; D010165:Palladium