Monoalkylation of Schiff Bases Derived from Glycine

1 Monoalkylation of Schiff Bases Derived from Glycine 

These reports have accelerated research into improvements of the asymmetric alkylation of 5, and have resulted in the emergence of a series of appropriately modified purely synthetic chiral quaternary ammonium salts. The performance of the representative catalysts in the asymmetric benzylation of 5 are summarized in Table 11.2, in order to facilitate for their preparative use. 

Entry Catalyst (X mol%) Base Solvent T(X) t(h) Yield (%) ee (%) (config.) Reference 

A recyclable fluorous chiral phase-transfer catalyst 36 has been developed by the present authors group and its high chiral efficiency and reusabihty demonstrated in the asymmetric alkylahon of 5. On completion of the reaction, 36 could be easily recovered by the simple extrachon with FC-72 (perfluorohexanes) as a fluorous 

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