An efficient strategy for the parallel solid-phase synthesis of 4,5-dihydro
-1H-1,4-benzddiazepine-2,3-diones is described. The reductive alkylation of
resin-bound primary amine with different substituted o-nitrobenzaldehydes
generated a secondary amine, which was treated further with methyl chloroox
oacetate. The nitro group was reduced with tin(II) chloride. During the ove
rnight reduction, an in situ intramolecular cyclization occurred to provide
, following HF cleavage, the desired 4,5-dihydro-1H-1,4-benzodiazepine-2,3-
dione. (C) 2001 Elsevier Science Ltd. All rights reserved.