Steroids and related natural products. XI. Reduction of esters to ethers

George Pettit, David M. Piatak

Research output: Contribution to journalArticle

65 Citations (Scopus)

Abstract

Direct reduction of dihydroabietic γ-lactone (Ia), the isomeric butyl esters (IIIb-d) of cholanic acid, and t-butyl-5α-pregnane 20S-carboxylic acid (Va) to the corresponding ethers (Ib, IVa, IVc, IVd, and VI) has been accomplished. Reduction was carried out using a reagent prepared from sodium borohydride and boron trifluoride, in diglyme-tetrahydrofuran. Boron trifluoride with either lithium aluminum hydride or lithium borohydride proved less satisfactory. Increasing conversion of the butyl esters (IIIb-d) to ethers (7-76% yield) was observed as the alcohol group varied from normal to tertiary. Similar reduction of 3β-formyloxy-5α-cholestane and 3β-formyloxy-5α-lanostane (VIIa) gave the corresponding 3β-methoxy steroids. The sensitivity of this unique ester → ether reduction reaction to structural variations in the ester group has been discussed.

Original languageEnglish (US)
Pages (from-to)2127-2130
Number of pages4
JournalJournal of Organic Chemistry
Volume27
Issue number6
StatePublished - 1962
Externally publishedYes

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Ethers
Biological Products
Esters
Steroids
Cholestanes
Pregnanes
Lactones
Carboxylic Acids
Ether
Alcohols
boron trifluoride

ASJC Scopus subject areas

  • Organic Chemistry

Cite this

Steroids and related natural products. XI. Reduction of esters to ethers. / Pettit, George; Piatak, David M.

In: Journal of Organic Chemistry, Vol. 27, No. 6, 1962, p. 2127-2130.

Research output: Contribution to journalArticle

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