Home > Community > In the Wittig reaction, why do stabilised ylides produce E-alkenes and unstabilised ylides produce Z-alkenes? [duplicate]
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Kevin McCarthy

In the Wittig reaction, why do stabilised ylides produce E-alkenes and unstabilised ylides produce Z-alkenes? [duplicate]

Asif Makhdoomi  Follow

I have given some justification on why unstabilized ylids give Z-alkenes in this answer of mine.

A possible explanation why stabilized ylids show E-selectivity is given in the organic chemistry textbook by Clayden, Warren, Wothers and Greeves on p. 817:

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Joe Jacobs  Follow
Why do stabilised ylids lead to trans alkenes in the Wittig reaction?More
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Hugh Mann  Follow
1ed, is generally no longer considered to be correct. Ive written up a summary of the experimental evidence and the currently accepted model for (E)-selectivity: More
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Joseph Braun  Follow
Organic ChemistryMore
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E. Milton Wilson  Follow
Just a disclaimer: this explanation, given in Clayden et al. More
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