Enantioselective Synthesis of β-Hydrazino Alcohols Using Alcohols and N-Boc-Hydrazine as Substrates
1School of Chemistry and Chemical Engineering, Beijing Institute of Technology , Beijing 100081, People's Republic of China.
Abstract:
An enantioselective approach for the synthesis of α-hydrazino aldehydes is described that utilizes alcohols and N-Boc hydrazine instead of the conventional combination of aldehydes with azodicarboxylates. This protocol is enabled by merging in situ aerobic dual oxidation with asymmetric organocatalysis. This reaction also exhibits a high tolerance for varieties of substituents on the alcohol component. This approach features excellent enantiocontrol, cheap starting materials, operational simplicity, and scalability. The corresponding chiral β-hydrazino alcohols were obtained by sequential reduction with excellent enantioselectivity (up to 98% ee).
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