Novel applications of alkyl fluorides in organic synthesis: Versatile nitrogen protecting groups

The potential of the 2-fluoroethyl group as a nitrogen protecting group was demonstrated. The stability of alkyl fluorides, such as 2-fluoroethyl, to a variety of reaction conditions, makes them attractive nitrogen protecting groups. The 2-fluoroethyl group was easily introduced, in good yields, by the treatment of the NH group with potassium carbonate and 2-bromo-1-fluoro ethane. Reaction of the 2-fluoroethyl group with boron tribromide resulted in the replacement of fluorine by bromine, to give the corresponding 2-brom oethyl group which was easily removed by known methods. (C) 1998 Elsevier S cience Ltd. All rights reserved.