There are also likely to be other possibilities involving organometallic syntheses. Many chiral agents have been developed for many syntheses involving these reactions. More information, I cannot produce, this is essentially all I know. My source (March's 5th) was very vague, and only consisting of about two sentences stating what I already stated.
Many of these catalysts revolve around the syntheses of alcohols and amines, so it is likely that such methods exist and are applicable here. What they are, I do not know as of yet.
PrimoPyro
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