We disclose the reductive trifluoromethylation of chemically stable homocystine and cystine to provide corresponding trifluoromethyl ethers by the CF3I/Na/Liq.NH3 system. Both non-protected and protected homocystines can be nicely converted into trifluoromethylated methionines under the same condition. The method described offers a robust synthesis of pharmaceutically important trifluoromethionine, suitable for multigram synthesis. Pentafluoroethylation of homocystine was also achieved by the CF3CF2I/Na/Liq.NH3 system. (C) 2011 Elsevier B.V. All rights reserved.