Science of Synthesis

Hodgson, D. M.; Humphreys, P. G., Science of Synthesis, (2008) 36, 643.

The chiral amides discussed in the previous section can be expensive, or are difficult to synthesize. Therefore a chiral amine that can be used catalytically in the presence of a stoichiometric amount of simple lithium amide or organolithium is desirable. The discovery that lithium (2S)-2-(pyrrolidin-1-ylmethyl)pyrrolidide (‌144‌) rearranges cyclohexene oxide more rapidly than lithium diisopropylamide is used in the first example of a catalytic asymmetric rearrangement of an epoxide to an allylic alcohol (‌Scheme 68‌).[‌331‌] The level of asymmetric induction achieved with the catalytic system (20 mol% ‌144‌) is essentially the same as that obtained using stoichiometric amounts of the chiral lithium amide ‌144‌.

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References