Some methods for innovative molecular transformations using optically active α-amino acids have been exploited. 1) The non-Kolbe reaction of the
N-benzoyloxazoline derivative
1 derived from L-serine gave the optically active
N,
O-acetal
2 when graphite was used an anode material. This reaction represents the first example of “memory of chirality” in the carbenium ion chemistry. 2) The optically active pipecolic acid derivative
13, prepared from L-lysine by using electrochemical oxidation, was cyclopropanated with high diastereoselectivity (96.6%de), and the product
14 was transformed into (2
S,3
R)-metanopipecolic acid (
7). 3) An enantiomerically pure 1,2-dihydropyridine
23 was prepared from L-lysine using electrochemical oxidation as a key step and was utilized as a chiral diene synthon in the Diels-Alder reaction. That is, in the presence of AlCl
3, the Diels-Alder reaction between
23 and
N-acryloyloxazolidinone
24 gave a cycloadduct with high stereoselectivity, which was converted to an optically active isoquinuclidine derivative
26 (96.8%ee). 4) The Hofmann rearrangement of the L-glutamine derivative
27 to the enantiomerically pure 2-aminobutyric acid derivative
28 was successfully achieved with an electrochemical method using a trifluoroethanol-MeCN solvent system. 5) Some types of
N-formyl cyclic amine derivatives were found to be effective activators of trichlorosilane to reduce ketones and imines. Namely, the reduction of ketones and imines by trichlorosilane with a catalytic amount of
L-proline derivatives
30 and
32 gave enantiomerically enriched
sec-alcohols and amines, respectively, to some extent of optical yields.
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