Elsevier, Journal of Organometallic Chemistry, 2(627), p. 135-138
DOI: 10.1016/s0022-328x(01)00719-7
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Reaction of racemic 3,3′,4,4′-tetramethyl-1,1′-diphosphaferrocene-2-carboxylic acid 1 with (S)-α-phenylethylamine in the presence of benzotriazol-1-yl-oxytris-(dimethylamino)phosphonium hexafluorophosphate and diisopropylethylamine leads to diastereomeric amides, (S,R)-2 and (S,S)-2. The diastereomers were separated by column chromatography and their absolute configurations were determined from NMR data supported by molecular modeling.