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Single Pot (single + pot)
Selected AbstractsA Modular Approach to ,-Arylated Carbonyl Compounds via Indium Tris(bistriflylamide)-Catalyzed Regioselective Addition of ,-Ketoesters to 1,3-DiynesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-13 2005Masaharu Nakamura Abstract A modular synthesis of ,-arylated carbonyl compounds has been achieved by the combination of an indium-catalyzed regioselective addition of ,-keto esters to conjugated diynes and a palladium-catalyzed benzannulation reaction. Indium tris(bistriflylamide), In(NTf2)3, was found to be an efficient catalyst for the first addition reaction of ,-keto esters to diynes. The reaction proceeds with perfect regioselectivity to give conjugated enynes in high yield. The second palladium-catalyzed benzannulation proceeds in high to excellent yield and with high regioselectivity for a variety of diynes. This two-step ,-arylation of carbonyl compounds thus proceeds in a catalytic manner without loss of elements in the starting materials. The reaction may be performed in a single pot without isolation of the product of the first step. [source] Comparison of single pot and multiphase high shear wet granulation processes related to excipient compositionJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 10 2009K. Giry Abstract At present time, industrial production imperatives can require the transposition of a formulation from one equipment to another. In order to evaluate the impact of such a switch on the properties of granules and tablets, investigations were undertaken on formulations manufactured both in a single pot mixer-granulator-dryer (high shear granulator with in situ double jacket vacuum drying) and in a multiphase equipment (high shear granulator/fluid bed dryer). Principal component analysis highlighted the major contribution of the binder ratio on granule size distribution, flow and packing ability whereas the relative ratio of mannitol and lactose, used as fillers, mainly impacted on compressibility and tablet cohesion. In the studied domain, the lubricant ratio did not explain the considered responses. Statistical analysis (comparison of means, analysis of variance and PCA) showed that both processes led to products with similar characteristics which demonstrated the ability of the processes to produce granules with close quality. However, Fielder®/Niro® granule characteristic data were found to be more dispersed, thus demonstrating a higher sensitivity of the multiphase process to formulation changes. Technological properties of granules and tablets were found to be maintained or improved therefore securing the switch from single pot to multiphase equipments. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:3761,3775, 2009 [source] Molecular Materials with Contrasting Optical Responses from a Single-Pot Reaction and Fluorescence Switching in a Carbon AcidCHEMISTRY - A EUROPEAN JOURNAL, Issue 12 2009A. Patra Abstract Three for the price of one: The reaction of tetracyanoquinodimethane with an aromatic amine is shown to follow an unusual course leading to three products in a single pot. The product molecules form a family of materials with contrasting optical responses, in that they exhibit light emission of different colors and emission switching that is sensitively triggered by acidic/basic environments (see scheme). A wide variety of amines are known to react with 7,7,8,8-tetracyanoquinodimethane (TCNQ) to yield push,pull diaminodicyanoquinodimethanes with a strongly zwitterionic structure and significant optical and nonlinear optical properties. A novel course of reaction is observed now with the amine 2-methyl-4-chloroaniline, which leads to three well-defined products, A,C, in a single pot. A and B are formed through the replacement of one cyano group in TCNQ by the amine; A is a carbon acid and B is its corresponding salt. C is the conventional product in which two cyano groups in TCNQ are replaced by the amine. The products are characterized structurally and spectroscopic studies reveal contrasting optical responses. A is nonfluorescent, whereas B and C show red and green emission, respectively, in the solution and solid states. The acid/conjugate-base pair A and B can be interconverted through facile, reversible, and repeated deprotonation/protonation cycles, which are accompanied by instantaneous switching of the fluorescence. The current study illustrates an interesting case of a single-pot reaction yielding different optical materials with attributes that can be switched through simple approaches such as protonation or tuned through modification of the push,pull characteristics. [source] | ||||||||||