Carbonylation of various organolithium reagents. A novel approach to heterocycles via intramolecular trapping of aromatic acyllithiums
作者:Keith Smith、Gamal A. El-Hiti、Gareth J. Pritchard、Anna Hamilton
DOI:10.1039/a903467f
日期:——
Doubly lithiated N-pivaloylanilines react smoothly with carbon monoxide at 0 °C to give 3-tert-butyl-3-hydroxy-2,3-dihydroindol-2-ones in good yields. Similarly, carbonylation of doubly lithiated 4-pivaloylamino- and 2-pivaloylaminopyridines at 0 °C affords the corresponding 5-aza- and 7-aza-3-tert-butyl-3-hydroxy-2,3-dihydroindol-2-ones, respectively, in good yields. However, carbonylation of doubly lithiated N-pivaloyl-o-toluidines takes a different course due to direct intramolecular cyclisation of the dilithio reagents to afford 2-tert-butylindoles without uptake of carbon monoxide.
双锂化的N-派伐酰苯胺在0°C下与一氧化碳反应,得到3-叔丁基-3-羟基-2,3-二氢吲哚-2-酮,产率良好。同样,在0°C下双锂化的4-派伐酰氨基和2-派伐酰氨基吡啶的羰基化反应分别生成相应的5-氮和7-氮-3-叔丁基-3-羟基-2,3-二氢吲哚-2-酮,产率同样良好。然而,双锂化的N-派伐酰-o-甲苯胺的羰基化反应则呈现不同的路径,因为锂酮试剂发生直接的分子内环化,生成2-叔丁基吲哚,而不吸收一氧化碳。