Ureidopeptide‐Based Brønsted Bases: Design,Synthesis and Application to the Catalytic Enantioselective Synthesis of β‐Amino Nitriles from (Arylsulfonyl)acetonitriles

The addition of cyanoalkyl moieties to imines is a very attractive method for the preparation of β‐amino nitriles. We present a highly efficient organocatalytic methodology for the stereoselective synthesis of β‐amino nitriles, in which the key to success is the use of ureidopeptide‐based Brønsted base catalysts in combination with (arylsulfonyl)acetonitriles as synthetic equivalents of the acetonitrile anion. The method gives access to a variety of β‐amino nitriles with good yields and excellent enantioselectivities, and broadens the stereoselective Mannich‐type methodologies available for their synthesis.