Heterogeneous catalysis for organic synthesis under continuous‐flow conditions becomes possible by a new reactor‐based approach. Continuous‐flow reactors with a monolithic glass/polymer composite interior are loaded with palladium particles by ion exchange followed by reduction. When incorporated into a continuous‐flow setup (PASSflow) this reactor allows the transfer‐hydrogenation of alkenes, alkynes, nitro‐substituted aromatic compounds and benzyl ethers in the flow‐through mode. In addition, the activity of the catalysts is well suited to achieve Suzuki, Sonogashira and Heck cross‐coupling reactions in the absence of phosphanes or any other ligands, resulting in a greatly simplified purification. As an extension to this concept a bifunctional support was prepared inside the reactor consisting of Pd particles and an ion‐exchange group (hydroxide form). In the Suzuki− Miyaura reaction the reactor serves as a base for immobilisation and activation of the boronic acid as boronate and as a catalyst for promoting the C−C coupling reaction under continuous‐flow conditions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

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The critical water activity (a w,c ) at a fixed temperature and transition temperature (T t ) in water between an anhydrate and its corresponding hydrate determine their physical stability. Hence, their accurate determination enables the efficient development of robust crystallization processes and formulation of drugs. The commonly used methods for determining the two parameters are either labor-and materialintensive or cannot be accurately measured due to slow kinetics. Thus, a material-sparing and fast method is desirable for adoption in the early stage of drug development when the materials and time are limited. In this study, we show that intrinsic dissolution rate (IDR) measurement is a fast (a few days) and material-sparing (<1 g) method for accurate determination of a w,c , T t , as well as free energy, enthalpy, and entropy of hydration. Overall, the IDR measurement is an advantageous technique for characterizing the stability of pharmaceutical hydrates in an early stage of drug development.

A procedure for the quantitative determination of ambroxol hydrochloride in its commercial injection based on the conjunction of Raman spectroscopy and chemometrics is described.

ticles. -Continuous-flow applications of palladium(0) catalysts are studied by use of the ionic exchange functionality of reactors with a monolithic glass/polymer composite interior for specifically positioning the catalyst inside the reactor. Palladium(0)-loaded continuous-flow reactors are successfully applied in transfer hydrogenation reactions of alkenes, alkynes, nitro-substituted aromatic compounds and benzyl ethers, and in Heck and Sonogashira reactions (to be continued). -(SOLODENKO, W.; WEN, H.; LEUE, S.; STUHLMANN, F.; SOURKOUNI-ARGIRUSI, G.; JAS, G.; SCHOENFELD, H.; KUNZ, U.; KIRSCHNING*, A.; Eur.