Application of directed metalation in synthesis. Part 6: A novel anionic rearrangement under directed metalation conditions leading to heteroannulation
作者:Tarun Kanti Pradhan、Chandrani Mukherjee、Sukanta Kamila、Asish De
DOI:10.1016/j.tet.2004.04.033
日期:2004.6
from easily available phenols is described. The key step in this synthesis is a hitherto unreported anionic rearrangement under directed metalation conditions. The rearrangement occurs after side chain deprotonation of a methyl sulfanyl group by an O-carbamate directed metalating group and the reaction mixture is kept at room temperature for 8–12 h. Acid-mediated cyclisation of the rearranged product
描述了由容易获得的酚的短而有效的合成缩合的1,4-氧杂噻吩-2-酮。该合成过程中的关键步骤是在定向金属化条件下迄今未报道的阴离子重排。重排由甲基硫烷基的侧链的去质子化之后发生ø -氨基甲酸酯定向组金属化而得,并且将反应混合物在室温下保持8-12小时。重排产物的酸介导的环化作用提供[1,4]草苷-2-一。