Synthesis of all four enantiomers of 1-aminoindane-2-carboxylic acid, a new cispentacin benzologue

Racemic cis- and trans-1-aminoindane-2-carboxylic acids (3 and 5) were prepared from indene by chlorosulphonyl isocyanate addition followed by ring opening and isomerisation. The intermediate racemic hydroxymethylated beta -lactam 6 was resolved through the lipase-catalysed asymmetric acylation of the primary hydroxy group at the (R)-stereogenic centre. High enantioselectivities (E>200) were observed when the enzymatic reactions were performed with lipase AK or lipase PS as catalyst and vinyl acetate or vinyl butyrate as acyl donor. The hydrolysis and isomerisation resulted in all four enantiomers (9, 11, 13 and 14) of 1-aminoindane-2-carboxylic acid, a new benzologue of cispentacin. (C) 2000 Elsevier Science Ltd. All rights reserved.