A Simplified Synthesis of Takemoto’s Catalyst

Abstract

A facile two-step procedure for the preparation of Takemoto’s catalyst is reported. The thiourea moiety was obtained by condensation of 3,5-bis(trifluoromethyl)aniline with phenyl chlorothioformate and in situ substitution of phenol by trans-1,2-diaminocyclohexane. Subsequent reductive dimethylation using formaldehyde/zinc afforded Takemoto’s catalyst.

organocatalyst - thiourea - amine - bifunctional

References

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