Enantiospecific sp<sup>2</sup>
-sp<sup>3</sup>
Coupling of <i>ortho</i>
- and <i>para</i>
-Phenols with Secondary and Tertiary Boronic Esters
作者:Claire M. Wilson、Venkataraman Ganesh、Adam Noble、Varinder K. Aggarwal
DOI:10.1002/anie.201710777
日期:2017.12.18
The coupling of ortho- and para-phenols with secondary and tertiary boronic esters has been explored. In the case of para-substituted phenols, after reaction of a dilithio phenolate species with a boronic ester, treatment with Ph3 BiF2 or Martin's sulfurane gave the coupled product with complete enantiospecificity. The methodology was applied to the synthesis of the broad spectrum antibacterial natural
邻位酚和对位酚与仲硼酸酯和叔硼酸酯的偶联已被探索。对于对位取代酚,二锂硫代酚盐与硼酸酯反应后,用Ph3 BiF2 或马丁硫烷处理,得到具有完全对映专一性的偶联产物。该方法应用于广谱抗菌天然产物(-)-4-(1,5-二甲基己-4-烯基)-2-甲基苯酚的合成。对于邻位取代的苯酚,需要首先在苯酚氧原子上掺入苯并三唑。随后的邻位锂化和硼化得到偶联产物,同样具有完全的立体特异性。