NOVEL MEMBRANE-BASED PROCESS FOR THE PRODUCTION OF SUBSTITUTED BENZYL ALCOHOLS

THE USE OF PROTECTING GROUPS IS A VITAL TOOL IN THE SYNTHESIS OF MULTIFUNCTIONAL MOLECULES SUCH AS VALUABLE "NEWGENERATION" PHARMACEUTICALS. WHEN A REACTION MUST BE CARRIED OUT AT A SPECIFIC REACTION SITE, PROTECTING GROUPS ARE USED TO TEMPORARILY BLOCK OTHER SENSITIVE REACTION SITESON THE MOLECULE. SUBSTITUTED BENZYL ALCOHOLS ARE PARTICULARLY USEFUL AS PROTECTING GROUPS. THEY ARE PREPARED BY REACTING ELECTROPHILES WITH A SIMPLE DERIVATIVE OF BENZYL ALCOHOL, BENZYL ALCOHOL ESTER. ALTHOUGH THIS REACTION PROCEEDS IN EXCELLENT YIELD, IT RESULTS IN A MIXTURE OF ISOMERS WITH SIMILAR PHYSICAL PROPERTIES. SEPARATION OF THE ISOMERS IS TECHNICALLY DIFFICULT AND EXPENSIVE. THIS PROPOSAL IS AIMED TOWARD THE DEVELOPMENT OF A NOVEL MEMBRANE-BASED PROCESS TO ADDRESS THIS PROBLEM. THE SEPARATION PROCESS IS BASED ON A REGIOSELECTIVE CATALYST THAT SELECTIVELY HYDROLYZES 4-SUBSTITUTED BENZYL ALCOHOL ESTER, LEAVING 2-SUBSTITUTED BENZYL ALCOHOL ESTER UNCHANGED. BECAUSE THE PRODUCTS OF THE HYDROLYSIS REACTION HAVE DRAMATICALLY DIFFERENT PHYSICAL PROPERTIES, THEY SHOULDBE SIMPLE TO SEPARATE USING A MEMBRANE-BASED EXTRACTION/CONCENTRATION SYSTEM DEVELOPED PREVIOUSLY AT BENDRESEARCH. BASED ON PRELIMINARY RESULTS, THIS APPROACH WILL OFFER MAJORADVANTAGES OVER CONVENTIONAL PROCESSES, IN TERMS OF PRODUCTIVITY AND ECONOMICS. IN PHASE I, WE PLAN TO ESTABLISH THE TECHNICAL AND ECONOMIC FEASIBILITY OF THE PROPOSED MEMBRANE-BASED PROCESS TO PREPARE 2- AND 4-NITROBENZYL ALCOHOLS. BASED ON SUCCESS IN PHASE I, IN PHASE II WE WILL 1) EVALUATE THE APPLICATION OF THIS APPROACH TO THE PRODUCTION OF OTHER COMMERCIALLY VALUABLE SUBSTITUTED BENZYL ALCOHOLS, AND 2) OPTIMIZE THE PROCESS FORA SELECTED APPLICATION. PHASE II RESULTS WILL FORM THE BASIS FOR PHASE III COMMERCIALIZATION.