Highly Enantioselective Cycloisomerization of Enynes Catalyzed by Rhodium for the Preparation of Functionalized Lactams

✍ Scribed by Aiwen Lei; Jason P. Waldkirch; Minsheng He; Xumu Zhang

• Publisher: John Wiley and Sons
• Year: 2002
• Tongue: English
• Weight: 106 KB
• Volume: 41
• Category: Article
• ISSN: 0044-8249
• DOI: 10.1002/1521-3773(20021202)41:23<4526::aid-anie4526>3.0.co;2-k

✦ Synopsis

The rising demand for chiral raw materials, intermediates, and active ingredients in pharmaceuticals, agrochemicals, food additives, and fragrances provides the impetus for rapid developments in chiral technology. [1] It remains a huge challenge for organic chemists to develop highly enantiose-lective reactions for the preparation of enantiomerically pure compounds in a cost-effective manner. Lactams are a versatile motif in organic chemistry and when functionalized, lactams often either show biological activity themselves, or are important building blocks for biologically active molecules such as (þ)-a-allokainic acid, (þ)-a-kainic acid, [2] acromelic trifluoroacetic acid (0.012 mL). After stirring for 3 h, NEt 3 (three drops) and AcOEt (20 mL) were added. The solution was poured into saturated aqueous NaHCO 3 , the phases were separated, and the organic phase was washed (sat. aq. NaCl), dried (Na 2 SO 4 ), and concentrated. Yield: 50 mg (85 %). 1