Nitro aminocarboxylic acid

Retention of configuration s. 19, 17 y-Aminocarboxylic acids from 4-nitro-2-thiopbenecarboxylic acids... 

N-Subst. a-aminocarboxylic acids from nitro compounds and alcohols... 

Selective reduction. A soln. of borane in tetrahydrofuran added dropwise at -18 during 19 min. to a mixture of adipic acid monoethyl ester and tetrahydrofuran, stirred and allowed to warm to room temp, during 16 hrs. -> ethyl 6-hydroxy-hexanoate. Y 75-88%. - Other functional groups such as cyano, halogeno, keto, or nitro, are likewise retained during this highly convenient reduction. F. e., also reduction of sterically hindered acids, s. N. M. Yoon, H. C. Brown et al., J. Org. Chem. 38, 2786 (1973) 2-aminoalcohols from a-aminocarboxylic acids s. M. L. Anhoury et al., Soc. Perkin 11974,191 via reduction with aq. NaBH of enolesters obtained from the acids and N-ethyl-5-phenylisoxazolium 3 -sulfonate (s. Synth. Meth. 16, 448) s. P. L. Hall and R. B. Perfetti, J. Org. Chem. 39, 111 (1974). 

---