Thiol additions to acrylates by fluorous mixture synthesis: Relative control of elution order in demixing by the fluorous tag and the thiol substituent

All possible combinations of a series of three fluorous benzyl tags and three acrylates have been made. The resulting acrylate esters were combined in groups of three (one of each tag) and the resulting mixtures were reacted with a mixture of four thiols under standard conditions to effect conjugate addition. Analysis of the resulting libraries by fluorous hplc showed a primary separation based on the tag and revealed reliable secondary separations based on the thiol and the acrylate. The primary and secondary separations were used together in a preparative 'mixture of mixtures' experiment in which one of the tagged acrylate mixtures was reacted with a mixture of three thiols. The resulting nine component mixture was demixed by fluorous and reverse phase hplc and then detagged to give all nine final products in pure form. © 2001 Elsevier Science Ltd

Fluorous mixture synthesis: A fluorous-tagging strategy for the synthesis and separation of mixtures of organic compounds

The solution-phase synthesis of organic compounds as mixtures rather than in individual pure form offers efficiency advantages that are negated by the difficulty in separating and identifying the components of the final mixture. Here, a strategy for mixture synthesis that addresses these separation and identification problems is presented. A series of organic substrates was tagged with a series of fluorous tags of increasing fluorine content. The compounds were then mixed, and multistep reactions were conducted to make enantiomers or analogs of the natural product mappicine. The resulting tagged products were then demixed by fluorous chromatography (eluting in order of increasing fluorine content) to provide the individual pure components of the mixture, which were detagged to release the final products

Enantioselective synthesis of proline derivatives by 1,3-dipolar cycloadditions

Research devoted to the synthesis of highly substituted prolines, which are hepatitis C virus inhibitors, using 1,3-dipolar cycloadditions (1,3-DC) of azomethine ylides is described. In the first part, a diastereoselective approach using an inexpensive lactate-derived acrylate as dipolarophile is described. In the second part, our efforts using simple and easily accessible chiral silver(I) and gold(I) complexes as catalysts for enantioselective synthesis of proline derivatives are reviewed. In this case, chiral phosphoramidites and binap have been used as privileged ligands. Parallel to these experimental results, considerable effort was dedicated to run semiempirical density functional theory (DFT) calculations to explain and justify the stereoselectivity of each process.This work has been supported by the DGES of the Spanish Ministerio de Ciencia e Innovación (MICINN) (Consolider INGENIO 2010 CSD2007-00006, FEDER-CTQ2007-62771/BQU, and by the Hispano-Brazilian project PHB2008-0037-PC), Generalitat Valenciana (PROMETEO/2009/039), and by the University of Alicante (GITE-09020-UA)