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Phosphine/palladium-catalyzed syntheses of alkylidene phthalans, 3-deoxyisoochracinic acid, isoochracinic acid, and isoochracinol.

ABSTRACT: In this study we used sequential catalysis-PPh(3)--catalyzed nucleophilic addition followed by Pd(0)-catalyzed Heck cyclization--to construct complex functionalized alkylidene phthalans rapidly, in high yields, and with good stereoselectivities (E/Z ratios of up to 1:22). The scope of this Michael-Heck reaction includes substrates bearing various substituents around the alkylidene phthalan backbone. Applying this efficient sequential catalysis, we accomplished concise total syntheses of 3-deoxyisoochacinic acid, isoochracinic acid, and isoochracinol.

SUBMITTER: Fan YC

PROVIDER: S-EPMC3391320 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature

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Phosphine/palladium-catalyzed syntheses of alkylidene phthalans, 3-deoxyisoochracinic acid, isoochracinic acid, and isoochracinol.

Fan Yi Chiao YC Kwon Ohyun O

Organic letters 20120621 13

In this study we used sequential catalysis-PPh(3)--catalyzed nucleophilic addition followed by Pd(0)-catalyzed Heck cyclization--to construct complex functionalized alkylidene phthalans rapidly, in high yields, and with good stereoselectivities (E/Z ratios of up to 1:22). The scope of this Michael-Heck reaction includes substrates bearing various substituents around the alkylidene phthalan backbone. Applying this efficient sequential catalysis, we accomplished concise total syntheses of 3-deoxyi ...[more]

PMID: 22721256

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