The regioselective generation of arynes from polyhalogenobenzenes. An improved synthesis of syn- and anti-1,4,5,8,9,12-hexahydro-1,4:5,8:9,12-triepoxytriphenylene
作者:Françisco Raymo、Franz H. Kohnke、Francesca Cardullo、Ulrich Girreser、J.Fraser Stoddart
DOI:10.1016/s0040-4020(01)89874-4
日期:1992.1
5-dichlorobenzene 12, were investigated as 1,3-bis-, 1,4-bis-, and 1,3,5-tris-aryne precursors by using alkyllithiums and alkali metal amides as the metalating reagents. The arynes were trapped in Diels-Alder reactions with furan as the diene. The title compounds 3a/b are now readily available in two steps in 7% overall yield from 1,2,4,5-tetrabromobenzene 6.
卤代苯1,2,4,5-四溴苯6,六溴苯9,对二氯四溴苯11和1,2-二溴-4,5-二氯苯12被研究为1,3-bis-,1,4 -双-和1,3,5-三-芳烃前体,使用烷基锂和碱金属酰胺作为金属化试剂。芳烃以呋喃为二烯被困在Diels-Alder反应中。现在可以容易地分两步获得标题化合物3a / b,其从1,2,4,5-四溴苯6的总收率为7%。