ORGN 422 |
| The cyclization of enamines of the type shown in eq 1 is a useful method for preparing 4-quinolones; however, this reaction is typically low yielding and requires harsh conditions (T >150 oC). In order to circumvent these problems, we have developed a method for effecting this cyclization in high yields under mild conditions. A wide variety of functionalized anilines bearing electron withdrawing groups have been successfully cyclized to 4-quinolones in yields ranging from 80 to 98 %. In addition, the cyclization protocol was applicable to a host of heterocyclic amines to provide a diverse array of 4-quinolones and novel heterocycles in excellent yields.
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Process R&D and Practical Syntheses of Medicinal Agents
1:00 PM-4:40 PM, Tuesday, 12 September 2006 Moscone Center -- Room 132, Oral
Division of Organic Chemistry |
