“Instant Methylide” Modification of the Corey–Chaykovsky Epoxide Synthesis

Abstract

We report that Me₃S(O)⁺I⁻ (1) and Me₃S⁺I⁻ (2) form stable, dry mixtures with KOt-Bu and NaH, respectively, which remain stable upon prolonged storage (>1 year). The corresponding methylides (Me₂SO=CH₂ and Me₂S=CH₂) are generated upon addition of DMSO or DMSO/THF solutions of carbonyl compounds, cleanly affording epoxides via the Corey–Chaykovsky reaction in good yields and short reaction times (as short as 20 min when 1–2 mmol of various ketones and aldehydes were treated with a mixture of 1 and KOt-Bu at 50–60°C).

Keywords:

• Epoxide synthesis
• Corey–Chaykovsky reaction
• Sul-furylide

Acknowledgments

We are grateful for the generous financial support provided by: the Fordham University Clare Boothe Luce Scholars Program (support for ALD); Mr. Stephen Bepler and Mr. Jack Walton, Members of the Fordham College at Rose Hill Board of Visitors (support for MS); the Fordham University Collegiate Science and Technology Entry Program (CSTEP) (support for CTT and RG); Research Corporation Cottrell College Science Award No. C-3698; and the National Science Foundation's Division of Undergraduate Education through grant DUE #9650684.