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The title sequence starts from β,γ-unsaturated α-ketoesters and 1,3-cyclohexanediones in the presence of the optically active ligand DASQ.

Optically active 5-bromo-1,3-oxazinan-2-ones are synthesized with excellent enantioselectivities and good yields by using DBDMH as the bromine source.

Transamination of α-keto acids with transaminases and pyridoxamine phosphate is an important process to form optically active α-amino acids in biological systems. Various biomimetic transamination systems have been developed for carbonyl compounds including α-keto acid derivatives, fluoroalkyl ketones, and unactivated ketones with chiral vitamin B6 analogues, artificial transaminase mimics, chiral nitrogen sources, and chiral catalysts. This review provides a brief summary of this area.

The oxidative azidation of indoles (I), (IV), and (VI) leads to desired spirocyclic 2-azido indolines.

An asymmetric biomimetic transamination process for β-branched α-keto esters (I) with a hydroquinine-derived chiral base and 4-cyano-benzylamine as the nitrogen source is reported.

Quinidine derivatives catalyze the asymmetric reductive amination of α-keto acetals with ortho-hydroxybenzylamine as nitrogen donor.

A quinine derivative is used as an efficient chiral catalyst for the asymmetric synthesis of trifluoromethyl aldimines (II) by [1,3]-proton shift of imines (I).

It is found that the chiral bases (QUI) and (ALK) efficiently promote the asymmetric transamination of α-keto esters.