Chiral Brpnsted Acid-Organocatalyzed Biginelli Reactions

1 Chiral Brpnsted Acid-Organocatalyzed Biginelli Reactions 

Interestingly, the authors also demonstrated the synthetic application of this catalytic asymmetric Biginelli methodology by the preparation of the active pharmaceutical ingredient monastrol 7 in two steps and with high optical purity (91% ee) from TBS-protected 3-hydroxybenzaldehyde, thiourea, and ethyl acetoacetate. 

SCHEME 9.10 Use of cyclic ketones 33 in the enantioselective Biginelli-like reaction. 

Scope of CYCLIC ketones in the Biginelli-like reaction  

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