MODIFIED ALUMINA CATALYST

摘要

The invention relates to a process for the preparation of an active alumina catalyst impregnated with a base, which is chosen from alkali or alkaline earth metals and its synthetic applications. The catalyst has been used for the protection of amines, alcohols and thiols with a wide variety of protecting agents. This procedure is widely applicable for N-protection of amino acids which finds wide industrial applications. The catalyst is also useful for carrying out nucleophilic substitutions of aromatic halides containing an electro-withdrawing group. A wide variety of nucleophilies chosen from amines, primary and secondary, aromatic and aliphatic, as well a s alcohols and thiols has been successfully employed. The methodology involves simple technique and easy work up procedure and is thus useful for large-sca le industrial preparations. Additionally the reactions avoid the use of harmful and thus satisfy the need for green chemistry.