General R 0010Phosphines Catalyzed Nucleophilic Addition of Azoles to Allenes: Synthesis of Allylazoles and Indolizines. -Triphenylphosphine readily catalyzes the umpolung addition of various azoles (I) to electron-deficient allenes (II). The reaction proceeds efficiently under neutral conditions and affords heterocycle-substituted Michael olefins (III)/(IV) in good yields and with moderate to excellent E-selectivity. Starting from formylpyrrole (VIII), this addition can be combined with a cyclization reaction to furnish indolizines (IX) and (XI) in the presence of the more nucleophilic tributylphosphine. -(VIRIEUX*, D.; GUILLOUZIC, A.-F.; CRISTAU, H.-J.; Tetrahedron 62 (2006) 15, 3710-3720; Lab. Chim. Org., CNRS, Ec. Natl. Super. Chim., F-34053 Montpellier, Fr.; Eng.) -Mischke 30-101
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