Talk:Asymmetric nucleophilic epoxidation

" Both cis and trans enones form trans epoxides under nearly all nucleophilic epoxidation conditions "

Has anyone got a reference to directly support this? I am finding it hard pinning this down to any direct literature evidence through the usual channels (web of science, reaxys etc).

I ask because I've just tested this on a database of ~1.6 million reactions using a nice stereo reaction query tool (part of my PhD) and found precisely 2 example reactions of cis-enones giving trans-epoxides. In contrast I can find cis-enones to cis-epoxides (129 examples) and trans-enones to trans-epoxides (469 examples). The break down of the cis-enone to cis-epoxide results are: 30% alkoxylanthanide/BINOL/Ph3(P,As)O catalysts (so these don't count as this method is stereospecific); 17% various "unnamed" methods (I.e. too numerous for the quick survey); 17% Mn-salen cat/NaOCl; 13% phase transfer quaternary ammonium catalysts + peroxide; 13% direct use of peroxides without catalysts. The 2 examples for cis-enones to trans-epoxide where both Julia-Colonna type reactions.

Thanks, Tony

Tonk777 (talk) 15:53, 7 September 2014 (UTC)