| abstract |
The present invention is related to the preparation of an active alumina catalyst impregnated with a base, which is selected from the group comprising alkali or alkaline earth metals and their synthetic applications. The catalyst has been used for the protection of amines, alcohols and thiols with a wide variety of protective agents. This procedure can be applied broadly for the N-protection of amino acids which find a wide variety of industrial applications. The catalyst is also useful for carrying out nucleophilic substitutions of aromatic halides containing an electron withdrawing group. A wide variety of nucleophiles chosen from the group comprising aminos, primary and secondary, aromatic and aliphatic, as well as alcohols and thiols have been used successfully. The methodology involves technically simple procedures and simple initial procedures and is therefore useful for large-scale industrial preparations. Additionally the reactions avoid the use of harmful substances and therefore satisfy the need for "green chemistry". |