Thio ureas as Co-catalyst

Hydrogen-bonding interaction plays a crucial role in the molecular recognition and activation processes of various biologically important reactions that are 

Although the MBH reactions of aliphatic aldehydes with 2-cyclohexen-l-one have achieved very high yields and ees by employing the organocatalysts 

R = c-pent, c-hexyl, i-Pr, PhCH2CH2, cinnamyl, Ph, 2-CIPh, 4-MeOPh 

In screening thiourea catalysts for the asymmetric aza-MBH reaction, Jacobsen et have developed a highly enantioselective catalytic aza-MBH reaction of various A-nosyl imines with methyl acrylate. High enantioselectivities 

Ar= Ph, 3-MePh, 3-MeOPh, 4-CIPh, 3-CIPh, 3-BrPh, 1-naphthyl, 2-thiophenyl, 3-furyl 

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