Synthesis of β ‐Amino Alcohols Using Ethyl 2‐Cyano‐2‐(2‐nitrobenzenesulfonyloxyimino)acetate ( o ‐NosylOXY)

We describe a mild and efficient method for the direct synthesis of β ‐amino alcohols from N‐ protected amino acids using ethyl‐2‐cyano‐2‐(2‐nitrophenylsulfonyloxyimino)acetate ( ortho ‐NosylOXY). The reaction sequence includes activation of carboxylic acid, followed by reduction with sodium borohydride, resulting in β ‐amino alcohols in good yields. This method is compatible with various N ‐protecting groups as well as the side chain protecting groups of amino acids. The excellent racemization suppression capability and recyclable nature of ortho ‐NosylOXY is an added feature to the in‐situ activation mediated carboxylic acid reduction.