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C-H bond functionalization via hydride transfer: direct coupling of unactivated alkynes and sp(3) C-H bonds catalyzed by platinum tetraiodide.

ABSTRACT: We report a catalytic intramolecular coupling between terminal unactivated alkynes and sp(3) C-H bonds via through-space hydride transfer (HT-cyclization of alkynes). This method enables one-step preparation of complex heterocyclic compounds by alpha-alkenylation of readily available cyclic ethers and amines. We show that PtI(4) is an effective Lewis acid catalyst for the activation of terminal alkynes for hydride attack and subsequent C-C bond formation. In addition, we have shown that the activity of neutral platinum salts (PtX(n)) can be modulated by the halide ligands. This modulation in turn allows for fine-tuning of the platinum center reactivity to match the reactivity and stability of selected substrates and products.

SUBMITTER: Vadola PA

PROVIDER: S-EPMC2971677 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature

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C-H bond functionalization via hydride transfer: direct coupling of unactivated alkynes and sp(3) C-H bonds catalyzed by platinum tetraiodide.

Vadola Paul A PA Sames Dalibor D

Journal of the American Chemical Society 20091101 45

We report a catalytic intramolecular coupling between terminal unactivated alkynes and sp(3) C-H bonds via through-space hydride transfer (HT-cyclization of alkynes). This method enables one-step preparation of complex heterocyclic compounds by alpha-alkenylation of readily available cyclic ethers and amines. We show that PtI(4) is an effective Lewis acid catalyst for the activation of terminal alkynes for hydride attack and subsequent C-C bond formation. In addition, we have shown that the acti ...[more]

PMID: 19852462

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