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Synthesis of alpha-keto-imides via oxidation of ynamides.

ABSTRACT: A de novo preparation of alpha-keto-imides via ynamide oxidation is described. With a number of alkyne oxidation conditions screened, a highly efficient RuO2-NaIO4 mediated oxidation and a DMDO oxidation have been identified to tolerate a wide range of ynamide types. In addition to accessing a wide variety of alpha-keto-imides, the RuO2-NaIO4 protocol provides a novel entry to the vicinal tricarbonyl motif via oxidation of push-pull ynamides, and imido acylsilanes from silyl-substituted ynamides. Chemoselective oxidation of ynamides containing olefins can be achieved by using DMDO, while the RuO2-NaIO4 protocol is not effective. These studies provide further support for the synthetic utility of ynamides.

SUBMITTER: Al-Rashid ZF

PROVIDER: S-EPMC2720040 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature

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Synthesis of alpha-keto-imides via oxidation of ynamides.

Al-Rashid Ziyad F ZF Johnson Whitney L WL Hsung Richard P RP Wei Yonggang Y Yao Pei-Yuan PY Liu Renhei R Zhao Kang K

The Journal of organic chemistry 20081021 22

A de novo preparation of alpha-keto-imides via ynamide oxidation is described. With a number of alkyne oxidation conditions screened, a highly efficient RuO2-NaIO4 mediated oxidation and a DMDO oxidation have been identified to tolerate a wide range of ynamide types. In addition to accessing a wide variety of alpha-keto-imides, the RuO2-NaIO4 protocol provides a novel entry to the vicinal tricarbonyl motif via oxidation of push-pull ynamides, and imido acylsilanes from silyl-substituted ynamides ...[more]

PMID: 18937407

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