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Sodium Diisopropylamide in Tetrahydrofuran: Selectivities, Rates, and Mechanisms of Alkene Isomerizations and Diene Metalations.

ABSTRACT: Sodium diisopropylamide in tetrahydrofuran is an effective base for the metalation of 1,4-dienes and isomerization of alkenes. Dienes metalate via tetrasolvated sodium amide monomers, whereas 1-pentene is isomerized by trisolvated monomers. Facile, highly Z-selective isomerizations are observed for allyl ethers under conditions that compare favorably to those of existing protocols. The selectivity is independent of the substituents on the allyl ethers; rate and computational data show that the rates, mechanisms, and roles of sodium-oxygen contacts are substituent-dependent. The competing influences of substrate coordination and solvent coordination to sodium are discussed.

SUBMITTER: Algera RF

PROVIDER: S-EPMC6059566 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Sodium Diisopropylamide in Tetrahydrofuran: Selectivities, Rates, and Mechanisms of Alkene Isomerizations and Diene Metalations.

Algera Russell F RF Ma Yun Y Collum David B DB

Journal of the American Chemical Society 20170814 33

Sodium diisopropylamide in tetrahydrofuran is an effective base for the metalation of 1,4-dienes and isomerization of alkenes. Dienes metalate via tetrasolvated sodium amide monomers, whereas 1-pentene is isomerized by trisolvated monomers. Facile, highly Z-selective isomerizations are observed for allyl ethers under conditions that compare favorably to those of existing protocols. The selectivity is independent of the substituents on the allyl ethers; rate and computational data show that the r ...[more]

PMID: 28735535

Similar Datasets

Sodium Diisopropylamide in Tetrahydrofuran: Selectivities, Rates, and Mechanisms of Arene Metalations.

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| S-EPMC2908497 | biostudies-literature

Exploring bis(cyclometalated) ruthenium(II) complexes as active catalyst precursors: room-temperature alkene-alkyne coupling for 1,3-diene synthesis.

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| S-EPMC4157063 | biostudies-literature

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