Fluorescent building blocks: Tetracarboxyamides with a central fluorescent diaminoterephthalate unit were prepared from succinyl succinates following a combinatorial-like strategy. The 2,5-diaminoterephthalates (see scheme; PG=protecting group) possess four points of diversification and are introduced as new scaffolds for combinatorial chemistry.2,5-Diaminoterephthalates that possess four points of diversification are introduced as new scaffolds for combinatorial chemistry. A straightforward synthesis of an orthogonally protected platform compound was developed. This platform was transformed by stepwise deprotection and amidation of the two amino and two carboxylic acid moieties into tetra-amides with a central aromatic ring as a fluorescence chromophore.

Bi(NO3)3‐catalyzed ring expansion of five‐membered ring 1,4‐diketones in the presence of primary amines leads to eight‐membered ring lactams. When applied to starting materials with a tetrahydrothiophene or pyrrolidine moiety, tetrahydro‐2H‐1,4‐thiazocin‐3‐ones and hexahydro‐1,4‐diazocin‐2‐ones are obtained as representatives of these very rare heterocyclic systems. In the case of tetrahydrofuran derivatives, other reaction conditions are required and yields of tetrahydro‐2H‐1,4‐oxazocin‐3‐ones are very low.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Eight-membered-ring lactams were prepared by the Bi-catalyzed reaction of 1,4-diketones with primary amines. These lactams define a new type of non-planar molecular scaffold with three points allowing for diversification, which were evaluated as the basis for combinatorial library synthesis. For this reason, reaction conditions were optimized, and the scope and limitations were investigated. After the Bi-catalyzed reaction, further diversification was achieved by ester

A New Synthesis of Sulfur-, Nitrogen-and Oxygen-Containing Eight-Membered Ring Lactams. -Bi-catalyzed ring expansion of phenylcarbonylmethyl-substituted tetrahydrothiophenones or pyrrolidinones (I) with aliphatic amines provides access towards eight-membered ring lactams (III) in moderate yields. The analogous reaction of tetrahydrofuranones proceeds under different conditions and gives only low yield of product lactam (V). -(PFLANTZ, R.; SLUITER, J.; KRICKA, M.; SAAK, W.; HOENKE, C.; CHRISTOFFERS*, J.; Eur.

Prepared by Ring-Expansion of 1,4-Diketones with Primary Amines. -A library of polyfunctionalized eight-membered lactams is prepared in an efficient approach involving the bismuth nitrate-catalyzed ring enlargement of aroylmethylcyclopentanones (I) with a wide variety of amines (II) to furnish lactams (III). Additional diversification is introduced by amide formation at the appendant ester group as demonstrated for derivatives (VII). -(PFLANTZ, R.; TIELMANN, P.; ROESSLE, M.; HOENKE, C.; CHRISTOFFERS*, J.; Eur.