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Regio- and stereoselective monoepoxidation of dienes using methyltrioxorhenium: synthesis of allylic epoxides.

ABSTRACT: Methyltrioxorhenium (MTO) complexed with pyridine was shown to be a highly effective catalyst for the regioselective monoepoxidation of conjugated di- and trienes using 30% H2O2 at or below room temperature. The resultant allylic epoxides, and the triols derived from them, are versatile synthetic intermediates as well as substructures present in many bioactive natural products. The site of epoxidation was dependent upon olefin substitution, olefin geometry (Z vs E), and the presence of electron-withdrawing substituents on adjacent carbons. For 1-acyl(silyl)oxypenta-2,4-dienes, epoxidation of the distal olefin was generally favored in contrast to the adjacent regioselectivity characteristic of Sharpless, peracid, and other directed epoxidations of hydroxylated dienes.

SUBMITTER: De SR

PROVIDER: S-EPMC4227570 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature

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Regio- and stereoselective monoepoxidation of dienes using methyltrioxorhenium: synthesis of allylic epoxides.

De Saroj Ranjan SR Kumar Ganesh G Jat Jawahar L JL Birudaraju Saritha S Lu Biao B Manne Rajkumar R Puli Narender N Adebesin Adeniyi Michael AM Falck John R JR

The Journal of organic chemistry 20141027 21

Methyltrioxorhenium (MTO) complexed with pyridine was shown to be a highly effective catalyst for the regioselective monoepoxidation of conjugated di- and trienes using 30% H2O2 at or below room temperature. The resultant allylic epoxides, and the triols derived from them, are versatile synthetic intermediates as well as substructures present in many bioactive natural products. The site of epoxidation was dependent upon olefin substitution, olefin geometry (Z vs E), and the presence of electron- ...[more]

PMID: 25321319

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