Micro-flow synthesis of β-amino acid derivatives via a rapid dual activation approach

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Both CbzCl and acylammonium cation are unstable,

therefore, we intended to convert them to a stable

amide using benzyl amine.

We examined substrate scope with the reaction time of

3.3 sec. Because yield was not changed by reducing the

reaction time from 10 sec to 3.3 sec in our preliminary

examination. Details, see SI.

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chloroformate was used instead of CbzCl for

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Synthesis of 4a under batch conditions afforded

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