2,5-Disubstituted furans were synthesized by one-flask Heck arylation/oxidation sequences. The starting materials are 2-substituted 2,3-dihydrofurans, conveniently available by RCM/isomerization sequences, and arenediazonium salts. These react in ligand-free Heck reactions to afford 2,5-disub-stituted 2,5-dihydrofurans, which are oxidized to the corresponding furans without isolation or intermediate
2,5-二取代
呋喃是通过单瓶 Heck 芳基化/氧化序列合成的。起始材料是 2-取代的
2,3-二氢呋喃,可通过 RCM/异构化序列方便地获得,以及
芳烃重氮盐。它们在无
配体的 Heck 反应中反应,得到 2,5-二取代的
2,5-二氢呋喃,无需分离或中间处理即可将其氧化为相应的
呋喃。根据底物的不同,可以使用
氯苯醌或
DDQ 方便地实现氧化。