摘要 |
<p>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 as alcohols and thiols has been successfully employed. The methodology involves simple technique and easy work up procedure and is thus useful for large-scale industrial preparations. Additionally the reactions avoid the use of harmful and thus satisfy the need for green chemistry.</p> |