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Gold-catalyzed formal [4? + 2?]-cycloadditions of propiolate derivatives with unactivated nitriles.

ABSTRACT: Gold-catalyzed hetero-[4? + 2?]-cycloadditions of tert-butyl propiolates with unactivated nitriles are described; the resulting 6H-1,3-oxazin-6-ones are not easily accessible via conventional methods. This new finding enables a one-pot gold-catalyzed synthesis of highly substituted pyridines through sequential gold-catalyzed reactions of tert-butyl propiolates with nitriles, and then with electron-deficient alkynes in the same solvent. The utility of these [4 + 2]-cycloadditions is further expanded with various aldehydes, ketones and 2-phenyloxetane, yielding satisfactory yields of cycloadducts.

SUBMITTER: Karad SN

PROVIDER: S-EPMC5950837 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Gold-catalyzed formal [4π + 2π]-cycloadditions of propiolate derivatives with unactivated nitriles.

Karad Somnath Narayan SN Chung Wei-Kang WK Liu Rai-Shung RS

Chemical science 20150720 10

Gold-catalyzed hetero-[4π + 2π]-cycloadditions of tert-butyl propiolates with unactivated nitriles are described; the resulting 6H-1,3-oxazin-6-ones are not easily accessible via conventional methods. This new finding enables a one-pot gold-catalyzed synthesis of highly substituted pyridines through sequential gold-catalyzed reactions of tert-butyl propiolates with nitriles, and then with electron-deficient alkynes in the same solvent. The utility of these [4 + 2]-cyc ...[more]

PMID: 29861918

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