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Regioselective synthesis of multisubstituted furans via metalloradical cyclization of alkynes with ?-diazocarbonyls: construction of functionalized ?-oligofurans.

ABSTRACT: Co(III)-carbene radicals generated from activation of ?-diazocarbonyls by Co(II)-porphyrin complexes have been shown to undergo a new type of tandem radical addition reaction with alkynes that affords five-membered furan structures. The Co(II) complex of 3,5-Di(t)Bu-IbuPhyrin, [Co(P1)], is effective in catalyzing the metalloradical cyclization reaction under neutral and mild conditions. The [Co(P1)]-catalyzed process tolerates a wide range of ?-diazocarbonyls and terminal alkynes with varied steric and electronic properties, producing polyfunctionalized furans with complete regioselectivity. The catalytic synthesis features a high degree of functional group tolerance and can be applied iteratively to construct functionalized ?-oligofurans.

SUBMITTER: Cui X

PROVIDER: S-EPMC3531582 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature

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Regioselective synthesis of multisubstituted furans via metalloradical cyclization of alkynes with α-diazocarbonyls: construction of functionalized α-oligofurans.

Cui Xin X Xu Xue X Wojtas Lukasz L Kim Martin M MM Zhang X Peter XP

Journal of the American Chemical Society 20121203 49

Co(III)-carbene radicals generated from activation of α-diazocarbonyls by Co(II)-porphyrin complexes have been shown to undergo a new type of tandem radical addition reaction with alkynes that affords five-membered furan structures. The Co(II) complex of 3,5-Di(t)Bu-IbuPhyrin, [Co(P1)], is effective in catalyzing the metalloradical cyclization reaction under neutral and mild conditions. The [Co(P1)]-catalyzed process tolerates a wide range of α-diazocarbonyls and terminal alkynes with varied ste ...[more]

PMID: 23205846

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