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36.5.1.14.1 Variation 1: Using Nonenantioselective Boron Reagents

DOI: 10.1055/sos-SD-036-00485

Hodgson, D. M.; Humphreys, P. G.Science of Synthesis, (200836606.

The most widely known method for the 1,2-reduction of an α,β-unsaturated ketone uses sodium borohydride and cerium(III) chloride in methanol (Luche reduction).[‌117‌] Under these conditions, the selective reduction of the enone chromophore may now occur even in the presence of an aldehyde group.[‌118‌] This contrasts with reductions using sodium borohydride in the absence of a lanthanide salt, which are typically unselective and form some of the corresponding alcohol and the saturated ketone by 1,4-addition of hydrogen. The presence of erbium(III) trichloride as the additive allows the selective reduction of α,β-unsaturated aldehydes in the presence of a nonconjugated aldehyde function.[‌119‌] Luche reactions can also be run in aqueous media and, in certain cases, this results in increased rates of reaction relative to those carried out in methanol.[‌120‌]

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Meeeeeeeeeee Meeeeeeee

(8M,8M)-()-eee-Meeeeee (88); Meeeeee Meeeeeeee:[‌888‌]

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