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Ni(II) salts and 2-propanol effect catalytic reductive coupling of epoxides and alkynes.

ABSTRACT: A Ni-catalyzed reductive coupling of alkynes and epoxides using Ni(II) salts and simple alcohol reducing agents is described. Whereas previously reported conditions relied on Ni(cod)(2) and Et(3)B, this system has several advantages including the use of air-stable and inexpensive Ni(II) precatalysts (e.g., NiBr(2)·3H(2)O) as the source of Ni(0) and simple alcohols (e.g., 2-propanol) as the reducing agent. Deuterium-labeling experiments are consistent with oxidative addition of an epoxide C-O bond that occurs with inversion of configuration.

SUBMITTER: Beaver MG

PROVIDER: S-EPMC3148188 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature

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Ni(II) salts and 2-propanol effect catalytic reductive coupling of epoxides and alkynes.

Beaver Matthew G MG Jamison Timothy F TF

Organic letters 20110630 15

A Ni-catalyzed reductive coupling of alkynes and epoxides using Ni(II) salts and simple alcohol reducing agents is described. Whereas previously reported conditions relied on Ni(cod)(2) and Et(3)B, this system has several advantages including the use of air-stable and inexpensive Ni(II) precatalysts (e.g., NiBr(2)·3H(2)O) as the source of Ni(0) and simple alcohols (e.g., 2-propanol) as the reducing agent. Deuterium-labeling experiments are consistent with oxidative addition of an epoxide C-O bon ...[more]

PMID: 21718038

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