The conversion of L-phenylalanine to (s)-2-hydroxy- 3-phenylpropanoic acid: A simple, visual example of a stereospecific SN2 reaction

Journal of Chemical Education

Volumn 87, Issue 6, 2010, Pages 623-624

  Van Draanen, Nanine A ^a   Hengst, Stephanie ^a  

^a CALIFORNIA LUTHERAN UNIVERSITY   (United States)

Author keywords

Acids Bases; Amino Acids; Chirality Optical Activity; Enantiomers; Hands On Learning Manipulatives; Laboratory Instruction; NMR Spectroscopy; Nucleophilic Substitution; Organic Chemistry; Reactions; Second Year Undergraduate; Synthesis

Indexed keywords

EID: 77955868776     PISSN: 00219584     EISSN: None     Source Type: Journal    
DOI: 10.1021/ed100167k     Document Type: Article

References (8)

1. A preparative SN2 reaction yielding a racemic mixture is described in Stabile, R. G.; Dicks, A. P. J. Chem. Educ. 2003, 80, 313.
2. An example of blended SN1/SN2 mechanisms yielding partially racemized products can be found in Mosher, M. D.; Kelly, C. O.; Mosher, M. W.J. Chem. Educ. 1996, 73, 567.
3. A recent lab experiment describing an achiral SN2 reaction can be found in Esteb, J. J.; Magers, J. R.;McNulty, L.A.; Morgan, P.; Wilson, A. M. J. Chem. Educ. 2009, 86,850.
4. Yoshikoshi, A. Kagaku, Zokan ( Kyoto, Jpn) 1981, 91, 87.
5. Nakahara,Y.; Ogawa, T. Kagaku, Zokan ( Kyoto, Jpn) 1981, 91, 101.
6. Brewster, P.; Hiron, F.; Hughes, E. D.; Ingold, C. K.; Rao, P. A.D. S.Nature 1950, 166, 179-180.
7. The related double-inversion of Lglutamic acid has been reported in this Journal, see Markgraf, J. H.;Davis, H. A. J. Chem. Educ. 1990, 67, 173.
8. Smith, L. R.; Williams, H. J. J. Chem. Educ. 1979, 56, 696. The use of phenylalanine in placeof glutamic acid has the advantages of demonstrating both intra- andinter-molecular SN2 reactions (rather than two intramolecularreactions); the product crystallizes from aqueous solution, obviatingthe need for extraction and concentration steps; and the 1H NMRspectrum of the product gives a clear, readily understood example ofthe complex splitting seen with diastereotopic protons.