A scalable synthesis of (1R,3S,5R)-2-(tert-butoxycarbonyl)-2-azabicyclo[3.1.0]hexane-3-carboxylic acid

Abstract A stereoselective and scalable synthesis of (1 R ,3 S ,5 R )-2-( tert -butoxycarbonyl)-2-azabicyclo[3.1.0]hexane-3-carboxylic acid ( 3a ) is described. Key to the success of the devised route was the realization that the stereoselectivity of a cyclopropanation step could be controlled by the composition of the functional group at C-α.