Aza-Baylis–Hillman reaction

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Aza-Baylis-Hillman reaction
Named after Anthony B. Baylis
Melville E. D. Hillman
Reaction type Coupling reaction
Identifiers
RSC ontology ID RXNO:0000264

The aza-Baylis–Hillman reaction or aza-BH reaction in

BINOL and phosphinyl BINOL compounds,[1] for example in the reaction of n-(4-chloro-benzylidene)-benzenesulfonamide with methyl vinyl ketone (MVK) in cyclopentyl methyl ether and toluene
at -15°C.

In one study a

racemisation
process simply by mixing chiral aza-BH adduct, phosphine and acid.

A reaction mechanism for an aza-BH reaction. The Ph represents a phenyl group; the Tos represents a tosyl group.

Asymmetric aza-BH

Aza-BH reactions are known in

chiral ligands. In one study,[3] for the first time, successful use was made of a chiral solvent based on an ionic liquid
(IL).

Synthesis of chiral ionic liquid, oct = octyl group

This solvent is a condensation product of L-(−)-

ammonium salt the resulting ionic liquid has a melting point
of −32°C.

Aza BH reaction in chiral ionic liquid, Ph = phenyl, Ts = tosyl

This IL serves as the chiral solvent for the aza-BH reaction between N-(4-bromobenzylidene)-4-toluenesulfonamide and

chemical yield 34–39% and enantiomeric excess
71–84%.

References

External links