Lithium Hexafluorophosphate-Catalyzed Efficient Tetrahydropyranylation of Tertiary Alcohols under Mild Reaction Conditions

Abstract

Lithium hexafluorophosphate is found to be an efficient catalyst for the tetrahydropyranylation of tertiary alcohols with dihydropyran under mild reaction conditions.

Key words

alcohols - Lewis acids - lithium hexafluorophosphate - protecting groups - tetrahydropyranylation

References

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15

The use of KPF₆ instead of LiPF₆ did not affect the protection at all.

16

The Lewis acidity of lithium ion decreases when lithium ion is stabilized by coordinative solvation.

17

Although testosterone is slightly soluble in hexane, quantitative tetrahydropyranylation was possible by using longer reaction times.

18

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